1 /*
2 * Copyright (c) 1997, 2020, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "aot/aotLoader.hpp"
28 #include "classfile/classFileParser.hpp"
29 #include "classfile/classFileStream.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/classLoaderData.inline.hpp"
32 #include "classfile/javaClasses.hpp"
33 #include "classfile/moduleEntry.hpp"
34 #include "classfile/resolutionErrors.hpp"
35 #include "classfile/symbolTable.hpp"
36 #include "classfile/systemDictionary.hpp"
37 #include "classfile/systemDictionaryShared.hpp"
38 #include "classfile/verifier.hpp"
39 #include "classfile/vmSymbols.hpp"
40 #include "code/dependencyContext.hpp"
41 #include "compiler/compileBroker.hpp"
42 #include "gc/shared/collectedHeap.inline.hpp"
43 #include "interpreter/oopMapCache.hpp"
44 #include "interpreter/rewriter.hpp"
45 #include "jvmtifiles/jvmti.h"
46 #include "logging/log.hpp"
47 #include "logging/logMessage.hpp"
48 #include "logging/logStream.hpp"
49 #include "memory/allocation.inline.hpp"
50 #include "memory/iterator.inline.hpp"
51 #include "memory/metadataFactory.hpp"
52 #include "memory/metaspaceClosure.hpp"
53 #include "memory/metaspaceShared.hpp"
54 #include "memory/oopFactory.hpp"
55 #include "memory/resourceArea.hpp"
56 #include "memory/universe.hpp"
57 #include "oops/fieldStreams.inline.hpp"
58 #include "oops/constantPool.hpp"
59 #include "oops/instanceClassLoaderKlass.hpp"
60 #include "oops/instanceKlass.inline.hpp"
61 #include "oops/instanceMirrorKlass.hpp"
62 #include "oops/instanceOop.hpp"
63 #include "oops/klass.inline.hpp"
64 #include "oops/method.hpp"
65 #include "oops/oop.inline.hpp"
66 #include "oops/recordComponent.hpp"
67 #include "oops/symbol.hpp"
68 #include "prims/jvmtiExport.hpp"
69 #include "prims/jvmtiRedefineClasses.hpp"
70 #include "prims/jvmtiThreadState.hpp"
71 #include "prims/methodComparator.hpp"
72 #include "runtime/atomic.hpp"
73 #include "runtime/biasedLocking.hpp"
74 #include "runtime/fieldDescriptor.inline.hpp"
75 #include "runtime/handles.inline.hpp"
76 #include "runtime/javaCalls.hpp"
77 #include "runtime/mutexLocker.hpp"
78 #include "runtime/orderAccess.hpp"
79 #include "runtime/thread.inline.hpp"
80 #include "services/classLoadingService.hpp"
81 #include "services/threadService.hpp"
82 #include "utilities/dtrace.hpp"
83 #include "utilities/events.hpp"
84 #include "utilities/macros.hpp"
85 #include "utilities/stringUtils.hpp"
86 #ifdef COMPILER1
87 #include "c1/c1_Compiler.hpp"
88 #endif
89 #if INCLUDE_JFR
90 #include "jfr/jfrEvents.hpp"
91 #endif
92
93
94 #ifdef DTRACE_ENABLED
95
96
97 #define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
98 #define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
99 #define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
100 #define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
101 #define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
102 #define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
103 #define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
104 #define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
105 #define DTRACE_CLASSINIT_PROBE(type, thread_type) \
106 { \
107 char* data = NULL; \
108 int len = 0; \
109 Symbol* clss_name = name(); \
110 if (clss_name != NULL) { \
111 data = (char*)clss_name->bytes(); \
112 len = clss_name->utf8_length(); \
113 } \
114 HOTSPOT_CLASS_INITIALIZATION_##type( \
115 data, len, (void*)class_loader(), thread_type); \
116 }
117
118 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
119 { \
120 char* data = NULL; \
121 int len = 0; \
122 Symbol* clss_name = name(); \
123 if (clss_name != NULL) { \
124 data = (char*)clss_name->bytes(); \
125 len = clss_name->utf8_length(); \
126 } \
127 HOTSPOT_CLASS_INITIALIZATION_##type( \
128 data, len, (void*)class_loader(), thread_type, wait); \
129 }
130
131 #else // ndef DTRACE_ENABLED
132
133 #define DTRACE_CLASSINIT_PROBE(type, thread_type)
134 #define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
135
136 #endif // ndef DTRACE_ENABLED
137
138
139 static inline bool is_class_loader(const Symbol* class_name,
140 const ClassFileParser& parser) {
141 assert(class_name != NULL, "invariant");
142
143 if (class_name == vmSymbols::java_lang_ClassLoader()) {
144 return true;
145 }
146
147 if (SystemDictionary::ClassLoader_klass_loaded()) {
148 const Klass* const super_klass = parser.super_klass();
149 if (super_klass != NULL) {
150 if (super_klass->is_subtype_of(SystemDictionary::ClassLoader_klass())) {
151 return true;
152 }
153 }
154 }
155 return false;
156 }
157
158 // private: called to verify that k is a static member of this nest.
159 // We know that k is an instance class in the same package and hence the
160 // same classloader.
161 bool InstanceKlass::has_nest_member(InstanceKlass* k, TRAPS) const {
162 assert(!is_hidden(), "unexpected hidden class");
163 if (_nest_members == NULL || _nest_members == Universe::the_empty_short_array()) {
164 if (log_is_enabled(Trace, class, nestmates)) {
165 ResourceMark rm(THREAD);
166 log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
167 k->external_name(), this->external_name());
168 }
169 return false;
170 }
171
172 if (log_is_enabled(Trace, class, nestmates)) {
173 ResourceMark rm(THREAD);
174 log_trace(class, nestmates)("Checking nest membership of %s in %s",
175 k->external_name(), this->external_name());
176 }
177
178 // Check for a resolved cp entry , else fall back to a name check.
179 // We don't want to resolve any class other than the one being checked.
180 for (int i = 0; i < _nest_members->length(); i++) {
181 int cp_index = _nest_members->at(i);
182 if (_constants->tag_at(cp_index).is_klass()) {
183 Klass* k2 = _constants->klass_at(cp_index, THREAD);
184 assert(!HAS_PENDING_EXCEPTION || PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass()),
185 "Exceptions should not be possible here");
186 if (k2 == k) {
187 log_trace(class, nestmates)("- class is listed at nest_members[%d] => cp[%d]", i, cp_index);
188 return true;
189 }
190 }
191 else {
192 Symbol* name = _constants->klass_name_at(cp_index);
193 if (name == k->name()) {
194 log_trace(class, nestmates)("- Found it at nest_members[%d] => cp[%d]", i, cp_index);
195
196 // Names match so check actual klass. This may trigger class loading if
197 // it doesn't match though that should be impossible as it means one classloader
198 // has defined two different classes with the same name! A compiler thread won't be
199 // able to perform that loading but we can't exclude the compiler threads from
200 // executing this logic. But it should actually be impossible to trigger loading here.
201 Klass* k2 = _constants->klass_at(cp_index, THREAD);
202 assert(!HAS_PENDING_EXCEPTION || PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass()),
203 "Exceptions should not be possible here");
204 if (k2 == k) {
205 log_trace(class, nestmates)("- class is listed as a nest member");
206 return true;
207 }
208 else {
209 // same name but different klass!
210 log_trace(class, nestmates)(" - klass comparison failed!");
211 // can't have two names the same, so we're done
212 return false;
213 }
214 }
215 }
216 }
217 log_trace(class, nestmates)("- class is NOT a nest member!");
218 return false;
219 }
220
221 // Called to verify that k is a permitted subclass of this class
222 bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
223 Thread* THREAD = Thread::current();
224 assert(k != NULL, "sanity check");
225 assert(_permitted_subclasses != NULL && _permitted_subclasses != Universe::the_empty_short_array(),
226 "unexpected empty _permitted_subclasses array");
227
228 if (log_is_enabled(Trace, class, sealed)) {
229 ResourceMark rm(THREAD);
230 log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
231 k->external_name(), this->external_name());
232 }
233
234 // Check that the class and its super are in the same module.
235 if (k->module() != this->module()) {
236 ResourceMark rm(THREAD);
237 log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
238 k->external_name(), this->external_name());
239 return false;
240 }
241
242 if (!k->is_public() && !is_same_class_package(k)) {
243 ResourceMark rm(THREAD);
244 log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
245 k->external_name(), this->external_name());
246 return false;
247 }
248
249 // Check for a resolved cp entry, else fall back to a name check.
250 // We don't want to resolve any class other than the one being checked.
251 for (int i = 0; i < _permitted_subclasses->length(); i++) {
252 int cp_index = _permitted_subclasses->at(i);
253 if (_constants->tag_at(cp_index).is_klass()) {
254 Klass* k2 = _constants->klass_at(cp_index, THREAD);
255 assert(!HAS_PENDING_EXCEPTION, "Unexpected exception");
256 if (k2 == k) {
257 log_trace(class, sealed)("- class is listed at permitted_subclasses[%d] => cp[%d]", i, cp_index);
258 return true;
259 }
260 } else {
261 Symbol* name = _constants->klass_name_at(cp_index);
262 if (name == k->name()) {
263 log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
264 return true;
265 }
266 }
267 }
268 log_trace(class, sealed)("- class is NOT a permitted subclass!");
269 return false;
270 }
271
272 // Return nest-host class, resolving, validating and saving it if needed.
273 // In cases where this is called from a thread that cannot do classloading
274 // (such as a native JIT thread) then we simply return NULL, which in turn
275 // causes the access check to return false. Such code will retry the access
276 // from a more suitable environment later. Otherwise the _nest_host is always
277 // set once this method returns.
278 // Any errors from nest-host resolution must be preserved so they can be queried
279 // from higher-level access checking code, and reported as part of access checking
280 // exceptions.
281 // VirtualMachineErrors are propagated with a NULL return.
282 // Under any conditions where the _nest_host can be set to non-NULL the resulting
283 // value of it and, if applicable, the nest host resolution/validation error,
284 // are idempotent.
285 InstanceKlass* InstanceKlass::nest_host(TRAPS) {
286 InstanceKlass* nest_host_k = _nest_host;
287 if (nest_host_k != NULL) {
288 return nest_host_k;
289 }
290
291 ResourceMark rm(THREAD);
292
293 // need to resolve and save our nest-host class.
294 if (_nest_host_index != 0) { // we have a real nest_host
295 // Before trying to resolve check if we're in a suitable context
296 if (!THREAD->can_call_java() && !_constants->tag_at(_nest_host_index).is_klass()) {
297 log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
298 this->external_name());
299 return NULL; // sentinel to say "try again from a different context"
300 }
301
302 log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
303 this->external_name(),
304 _constants->klass_name_at(_nest_host_index)->as_C_string());
305
306 Klass* k = _constants->klass_at(_nest_host_index, THREAD);
307 if (HAS_PENDING_EXCEPTION) {
308 if (PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass())) {
309 return NULL; // propagate VMEs
310 }
311 stringStream ss;
312 char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
313 ss.print("Nest host resolution of %s with host %s failed: ",
314 this->external_name(), target_host_class);
315 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
316 const char* msg = ss.as_string(true /* on C-heap */);
317 constantPoolHandle cph(THREAD, constants());
318 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
319 CLEAR_PENDING_EXCEPTION;
320
321 log_trace(class, nestmates)("%s", msg);
322 } else {
323 // A valid nest-host is an instance class in the current package that lists this
324 // class as a nest member. If any of these conditions are not met the class is
325 // its own nest-host.
326 const char* error = NULL;
327
328 // JVMS 5.4.4 indicates package check comes first
329 if (is_same_class_package(k)) {
330 // Now check actual membership. We can't be a member if our "host" is
331 // not an instance class.
332 if (k->is_instance_klass()) {
333 nest_host_k = InstanceKlass::cast(k);
334 bool is_member = nest_host_k->has_nest_member(this, THREAD);
335 // exception is rare, perhaps impossible
336 if (!HAS_PENDING_EXCEPTION) {
337 if (is_member) {
338 _nest_host = nest_host_k; // save resolved nest-host value
339
340 log_trace(class, nestmates)("Resolved nest-host of %s to %s",
341 this->external_name(), k->external_name());
342 return nest_host_k;
343 } else {
344 error = "current type is not listed as a nest member";
345 }
346 } else {
347 if (PENDING_EXCEPTION->is_a(SystemDictionary::VirtualMachineError_klass())) {
348 return NULL; // propagate VMEs
349 }
350 stringStream ss;
351 ss.print("exception on member check: ");
352 java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
353 error = ss.as_string();
354 }
355 } else {
356 error = "host is not an instance class";
357 }
358 } else {
359 error = "types are in different packages";
360 }
361
362 // something went wrong, so record what and log it
363 {
364 stringStream ss;
365 ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
366 this->external_name(),
367 this->class_loader_data()->loader_name_and_id(),
368 k->external_name(),
369 k->class_loader_data()->loader_name_and_id(),
370 error);
371 const char* msg = ss.as_string(true /* on C-heap */);
372 constantPoolHandle cph(THREAD, constants());
373 SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
374 log_trace(class, nestmates)("%s", msg);
375 }
376 }
377 } else {
378 log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
379 this->external_name());
380 }
381
382 // Either not in an explicit nest, or else an error occurred, so
383 // the nest-host is set to `this`. Any thread that sees this assignment
384 // will also see any setting of nest_host_error(), if applicable.
385 return (_nest_host = this);
386 }
387
388 // Dynamic nest member support: set this class's nest host to the given class.
389 // This occurs as part of the class definition, as soon as the instanceKlass
390 // has been created and doesn't require further resolution. The code:
391 // lookup().defineHiddenClass(bytes_for_X, NESTMATE);
392 // results in:
393 // class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
394 // If it has an explicit _nest_host_index or _nest_members, these will be ignored.
395 // We also know the "host" is a valid nest-host in the same package so we can
396 // assert some of those facts.
397 void InstanceKlass::set_nest_host(InstanceKlass* host, TRAPS) {
398 assert(is_hidden(), "must be a hidden class");
399 assert(host != NULL, "NULL nest host specified");
400 assert(_nest_host == NULL, "current class has resolved nest-host");
401 assert(nest_host_error(THREAD) == NULL, "unexpected nest host resolution error exists: %s",
402 nest_host_error(THREAD));
403 assert((host->_nest_host == NULL && host->_nest_host_index == 0) ||
404 (host->_nest_host == host), "proposed host is not a valid nest-host");
405 // Can't assert this as package is not set yet:
406 // assert(is_same_class_package(host), "proposed host is in wrong package");
407
408 if (log_is_enabled(Trace, class, nestmates)) {
409 ResourceMark rm(THREAD);
410 const char* msg = "";
411 // a hidden class does not expect a statically defined nest-host
412 if (_nest_host_index > 0) {
413 msg = "(the NestHost attribute in the current class is ignored)";
414 } else if (_nest_members != NULL && _nest_members != Universe::the_empty_short_array()) {
415 msg = "(the NestMembers attribute in the current class is ignored)";
416 }
417 log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
418 this->external_name(),
419 host->external_name(),
420 msg);
421 }
422 // set dynamic nest host
423 _nest_host = host;
424 // Record dependency to keep nest host from being unloaded before this class.
425 ClassLoaderData* this_key = class_loader_data();
426 this_key->record_dependency(host);
427 }
428
429 // check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
430 // or we are k's nest_host - all of which is covered by comparing the two
431 // resolved_nest_hosts.
432 // Any exceptions (i.e. VMEs) are propagated.
433 bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
434
435 assert(this != k, "this should be handled by higher-level code");
436
437 // Per JVMS 5.4.4 we first resolve and validate the current class, then
438 // the target class k.
439
440 InstanceKlass* cur_host = nest_host(CHECK_false);
441 if (cur_host == NULL) {
442 return false;
443 }
444
445 Klass* k_nest_host = k->nest_host(CHECK_false);
446 if (k_nest_host == NULL) {
447 return false;
448 }
449
450 bool access = (cur_host == k_nest_host);
451
452 ResourceMark rm(THREAD);
453 log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
454 this->external_name(),
455 access ? "" : "NOT ",
456 k->external_name());
457 return access;
458 }
459
460 const char* InstanceKlass::nest_host_error(TRAPS) {
461 if (_nest_host_index == 0) {
462 return NULL;
463 } else {
464 constantPoolHandle cph(THREAD, constants());
465 return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
466 }
467 }
468
469 InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
470 bool is_hidden_or_anonymous = parser.is_hidden() || parser.is_unsafe_anonymous();
471 const int size = InstanceKlass::size(parser.vtable_size(),
472 parser.itable_size(),
473 nonstatic_oop_map_size(parser.total_oop_map_count()),
474 parser.is_interface(),
475 parser.is_unsafe_anonymous(),
476 should_store_fingerprint(is_hidden_or_anonymous));
477
478 const Symbol* const class_name = parser.class_name();
479 assert(class_name != NULL, "invariant");
480 ClassLoaderData* loader_data = parser.loader_data();
481 assert(loader_data != NULL, "invariant");
482
483 InstanceKlass* ik;
484
485 // Allocation
486 if (REF_NONE == parser.reference_type()) {
487 if (class_name == vmSymbols::java_lang_Class()) {
488 // mirror
489 ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
490 }
491 else if (is_class_loader(class_name, parser)) {
492 // class loader
493 ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
494 } else {
495 // normal
496 ik = new (loader_data, size, THREAD) InstanceKlass(parser, InstanceKlass::_kind_other);
497 }
498 } else {
499 // reference
500 ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
501 }
502
503 // Check for pending exception before adding to the loader data and incrementing
504 // class count. Can get OOM here.
505 if (HAS_PENDING_EXCEPTION) {
506 return NULL;
507 }
508
509 return ik;
510 }
511
512
513 // copy method ordering from resource area to Metaspace
514 void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
515 if (m != NULL) {
516 // allocate a new array and copy contents (memcpy?)
517 _method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
518 for (int i = 0; i < m->length(); i++) {
519 _method_ordering->at_put(i, m->at(i));
520 }
521 } else {
522 _method_ordering = Universe::the_empty_int_array();
523 }
524 }
525
526 // create a new array of vtable_indices for default methods
527 Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
528 Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
529 assert(default_vtable_indices() == NULL, "only create once");
530 set_default_vtable_indices(vtable_indices);
531 return vtable_indices;
532 }
533
534 InstanceKlass::InstanceKlass(const ClassFileParser& parser, unsigned kind, KlassID id) :
535 Klass(id),
536 _nest_members(NULL),
537 _nest_host(NULL),
538 _permitted_subclasses(NULL),
539 _record_components(NULL),
540 _static_field_size(parser.static_field_size()),
541 _nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
542 _itable_len(parser.itable_size()),
543 _nest_host_index(0),
544 _init_state(allocated),
545 _reference_type(parser.reference_type()),
546 _init_thread(NULL)
547 {
548 set_vtable_length(parser.vtable_size());
549 set_kind(kind);
550 set_access_flags(parser.access_flags());
551 if (parser.is_hidden()) set_is_hidden();
552 set_is_unsafe_anonymous(parser.is_unsafe_anonymous());
553 set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
554 false));
555
556 assert(NULL == _methods, "underlying memory not zeroed?");
557 assert(is_instance_klass(), "is layout incorrect?");
558 assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
559
560 // Set biased locking bit for all instances of this class; it will be
561 // cleared if revocation occurs too often for this type
562 if (UseBiasedLocking && BiasedLocking::enabled()) {
563 set_prototype_header(markWord::biased_locking_prototype());
564 }
565 }
566
567 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
568 Array<Method*>* methods) {
569 if (methods != NULL && methods != Universe::the_empty_method_array() &&
570 !methods->is_shared()) {
571 for (int i = 0; i < methods->length(); i++) {
572 Method* method = methods->at(i);
573 if (method == NULL) continue; // maybe null if error processing
574 // Only want to delete methods that are not executing for RedefineClasses.
575 // The previous version will point to them so they're not totally dangling
576 assert (!method->on_stack(), "shouldn't be called with methods on stack");
577 MetadataFactory::free_metadata(loader_data, method);
578 }
579 MetadataFactory::free_array<Method*>(loader_data, methods);
580 }
581 }
582
583 void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
584 const Klass* super_klass,
585 Array<InstanceKlass*>* local_interfaces,
586 Array<InstanceKlass*>* transitive_interfaces) {
587 // Only deallocate transitive interfaces if not empty, same as super class
588 // or same as local interfaces. See code in parseClassFile.
589 Array<InstanceKlass*>* ti = transitive_interfaces;
590 if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
591 // check that the interfaces don't come from super class
592 Array<InstanceKlass*>* sti = (super_klass == NULL) ? NULL :
593 InstanceKlass::cast(super_klass)->transitive_interfaces();
594 if (ti != sti && ti != NULL && !ti->is_shared()) {
595 MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
596 }
597 }
598
599 // local interfaces can be empty
600 if (local_interfaces != Universe::the_empty_instance_klass_array() &&
601 local_interfaces != NULL && !local_interfaces->is_shared()) {
602 MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
603 }
604 }
605
606 void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
607 Array<RecordComponent*>* record_components) {
608 if (record_components != NULL && !record_components->is_shared()) {
609 for (int i = 0; i < record_components->length(); i++) {
610 RecordComponent* record_component = record_components->at(i);
611 MetadataFactory::free_metadata(loader_data, record_component);
612 }
613 MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
614 }
615 }
616
617 // This function deallocates the metadata and C heap pointers that the
618 // InstanceKlass points to.
619 void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
620
621 // Orphan the mirror first, CMS thinks it's still live.
622 if (java_mirror() != NULL) {
623 java_lang_Class::set_klass(java_mirror(), NULL);
624 }
625
626 // Also remove mirror from handles
627 loader_data->remove_handle(_java_mirror);
628
629 // Need to take this class off the class loader data list.
630 loader_data->remove_class(this);
631
632 // The array_klass for this class is created later, after error handling.
633 // For class redefinition, we keep the original class so this scratch class
634 // doesn't have an array class. Either way, assert that there is nothing
635 // to deallocate.
636 assert(array_klasses() == NULL, "array classes shouldn't be created for this class yet");
637
638 // Release C heap allocated data that this points to, which includes
639 // reference counting symbol names.
640 release_C_heap_structures_internal();
641
642 deallocate_methods(loader_data, methods());
643 set_methods(NULL);
644
645 deallocate_record_components(loader_data, record_components());
646 set_record_components(NULL);
647
648 if (method_ordering() != NULL &&
649 method_ordering() != Universe::the_empty_int_array() &&
650 !method_ordering()->is_shared()) {
651 MetadataFactory::free_array<int>(loader_data, method_ordering());
652 }
653 set_method_ordering(NULL);
654
655 // default methods can be empty
656 if (default_methods() != NULL &&
657 default_methods() != Universe::the_empty_method_array() &&
658 !default_methods()->is_shared()) {
659 MetadataFactory::free_array<Method*>(loader_data, default_methods());
660 }
661 // Do NOT deallocate the default methods, they are owned by superinterfaces.
662 set_default_methods(NULL);
663
664 // default methods vtable indices can be empty
665 if (default_vtable_indices() != NULL &&
666 !default_vtable_indices()->is_shared()) {
667 MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
668 }
669 set_default_vtable_indices(NULL);
670
671
672 // This array is in Klass, but remove it with the InstanceKlass since
673 // this place would be the only caller and it can share memory with transitive
674 // interfaces.
675 if (secondary_supers() != NULL &&
676 secondary_supers() != Universe::the_empty_klass_array() &&
677 // see comments in compute_secondary_supers about the following cast
678 (address)(secondary_supers()) != (address)(transitive_interfaces()) &&
679 !secondary_supers()->is_shared()) {
680 MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
681 }
682 set_secondary_supers(NULL);
683
684 deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
685 set_transitive_interfaces(NULL);
686 set_local_interfaces(NULL);
687
688 if (fields() != NULL && !fields()->is_shared()) {
689 MetadataFactory::free_array<jushort>(loader_data, fields());
690 }
691 set_fields(NULL, 0);
692
693 // If a method from a redefined class is using this constant pool, don't
694 // delete it, yet. The new class's previous version will point to this.
695 if (constants() != NULL) {
696 assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
697 if (!constants()->is_shared()) {
698 MetadataFactory::free_metadata(loader_data, constants());
699 }
700 // Delete any cached resolution errors for the constant pool
701 SystemDictionary::delete_resolution_error(constants());
702
703 set_constants(NULL);
704 }
705
706 if (inner_classes() != NULL &&
707 inner_classes() != Universe::the_empty_short_array() &&
708 !inner_classes()->is_shared()) {
709 MetadataFactory::free_array<jushort>(loader_data, inner_classes());
710 }
711 set_inner_classes(NULL);
712
713 if (nest_members() != NULL &&
714 nest_members() != Universe::the_empty_short_array() &&
715 !nest_members()->is_shared()) {
716 MetadataFactory::free_array<jushort>(loader_data, nest_members());
717 }
718 set_nest_members(NULL);
719
720 if (permitted_subclasses() != NULL &&
721 permitted_subclasses() != Universe::the_empty_short_array() &&
722 !permitted_subclasses()->is_shared()) {
723 MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
724 }
725 set_permitted_subclasses(NULL);
726
727 // We should deallocate the Annotations instance if it's not in shared spaces.
728 if (annotations() != NULL && !annotations()->is_shared()) {
729 MetadataFactory::free_metadata(loader_data, annotations());
730 }
731 set_annotations(NULL);
732
733 if (Arguments::is_dumping_archive()) {
734 SystemDictionaryShared::remove_dumptime_info(this);
735 }
736 }
737
738 bool InstanceKlass::is_sealed() const {
739 return _permitted_subclasses != NULL &&
740 _permitted_subclasses != Universe::the_empty_short_array() &&
741 _permitted_subclasses->length() > 0;
742 }
743
744 bool InstanceKlass::should_be_initialized() const {
745 return !is_initialized();
746 }
747
748 klassItable InstanceKlass::itable() const {
749 return klassItable(const_cast<InstanceKlass*>(this));
750 }
751
752 void InstanceKlass::eager_initialize(Thread *thread) {
753 if (!EagerInitialization) return;
754
755 if (this->is_not_initialized()) {
756 // abort if the the class has a class initializer
757 if (this->class_initializer() != NULL) return;
758
759 // abort if it is java.lang.Object (initialization is handled in genesis)
760 Klass* super_klass = super();
761 if (super_klass == NULL) return;
762
763 // abort if the super class should be initialized
764 if (!InstanceKlass::cast(super_klass)->is_initialized()) return;
765
766 // call body to expose the this pointer
767 eager_initialize_impl();
768 }
769 }
770
771 // JVMTI spec thinks there are signers and protection domain in the
772 // instanceKlass. These accessors pretend these fields are there.
773 // The hprof specification also thinks these fields are in InstanceKlass.
774 oop InstanceKlass::protection_domain() const {
775 // return the protection_domain from the mirror
776 return java_lang_Class::protection_domain(java_mirror());
777 }
778
779 // To remove these from requires an incompatible change and CCC request.
780 objArrayOop InstanceKlass::signers() const {
781 // return the signers from the mirror
782 return java_lang_Class::signers(java_mirror());
783 }
784
785 oop InstanceKlass::init_lock() const {
786 // return the init lock from the mirror
787 oop lock = java_lang_Class::init_lock(java_mirror());
788 // Prevent reordering with any access of initialization state
789 OrderAccess::loadload();
790 assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
791 "only fully initialized state can have a null lock");
792 return lock;
793 }
794
795 // Set the initialization lock to null so the object can be GC'ed. Any racing
796 // threads to get this lock will see a null lock and will not lock.
797 // That's okay because they all check for initialized state after getting
798 // the lock and return.
799 void InstanceKlass::fence_and_clear_init_lock() {
800 // make sure previous stores are all done, notably the init_state.
801 OrderAccess::storestore();
802 java_lang_Class::clear_init_lock(java_mirror());
803 assert(!is_not_initialized(), "class must be initialized now");
804 }
805
806 void InstanceKlass::eager_initialize_impl() {
807 EXCEPTION_MARK;
808 HandleMark hm(THREAD);
809 Handle h_init_lock(THREAD, init_lock());
810 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
811
812 // abort if someone beat us to the initialization
813 if (!is_not_initialized()) return; // note: not equivalent to is_initialized()
814
815 ClassState old_state = init_state();
816 link_class_impl(THREAD);
817 if (HAS_PENDING_EXCEPTION) {
818 CLEAR_PENDING_EXCEPTION;
819 // Abort if linking the class throws an exception.
820
821 // Use a test to avoid redundantly resetting the state if there's
822 // no change. Set_init_state() asserts that state changes make
823 // progress, whereas here we might just be spinning in place.
824 if (old_state != _init_state)
825 set_init_state(old_state);
826 } else {
827 // linking successfull, mark class as initialized
828 set_init_state(fully_initialized);
829 fence_and_clear_init_lock();
830 // trace
831 if (log_is_enabled(Info, class, init)) {
832 ResourceMark rm(THREAD);
833 log_info(class, init)("[Initialized %s without side effects]", external_name());
834 }
835 }
836 }
837
838
839 // See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
840 // process. The step comments refers to the procedure described in that section.
841 // Note: implementation moved to static method to expose the this pointer.
842 void InstanceKlass::initialize(TRAPS) {
843 if (this->should_be_initialized()) {
844 initialize_impl(CHECK);
845 // Note: at this point the class may be initialized
846 // OR it may be in the state of being initialized
847 // in case of recursive initialization!
848 } else {
849 assert(is_initialized(), "sanity check");
850 }
851 }
852
853
854 bool InstanceKlass::verify_code(TRAPS) {
855 // 1) Verify the bytecodes
856 return Verifier::verify(this, should_verify_class(), THREAD);
857 }
858
859 void InstanceKlass::link_class(TRAPS) {
860 assert(is_loaded(), "must be loaded");
861 if (!is_linked()) {
862 link_class_impl(CHECK);
863 }
864 }
865
866 // Called to verify that a class can link during initialization, without
867 // throwing a VerifyError.
868 bool InstanceKlass::link_class_or_fail(TRAPS) {
869 assert(is_loaded(), "must be loaded");
870 if (!is_linked()) {
871 link_class_impl(CHECK_false);
872 }
873 return is_linked();
874 }
875
876 bool InstanceKlass::link_class_impl(TRAPS) {
877 if (DumpSharedSpaces && SystemDictionaryShared::has_class_failed_verification(this)) {
878 // This is for CDS dumping phase only -- we use the in_error_state to indicate that
879 // the class has failed verification. Throwing the NoClassDefFoundError here is just
880 // a convenient way to stop repeat attempts to verify the same (bad) class.
881 //
882 // Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
883 // if we are executing Java code. This is not a problem for CDS dumping phase since
884 // it doesn't execute any Java code.
885 ResourceMark rm(THREAD);
886 Exceptions::fthrow(THREAD_AND_LOCATION,
887 vmSymbols::java_lang_NoClassDefFoundError(),
888 "Class %s, or one of its supertypes, failed class initialization",
889 external_name());
890 return false;
891 }
892 // return if already verified
893 if (is_linked()) {
894 return true;
895 }
896
897 // Timing
898 // timer handles recursion
899 assert(THREAD->is_Java_thread(), "non-JavaThread in link_class_impl");
900 JavaThread* jt = (JavaThread*)THREAD;
901
902 // link super class before linking this class
903 Klass* super_klass = super();
904 if (super_klass != NULL) {
905 if (super_klass->is_interface()) { // check if super class is an interface
906 ResourceMark rm(THREAD);
907 Exceptions::fthrow(
908 THREAD_AND_LOCATION,
909 vmSymbols::java_lang_IncompatibleClassChangeError(),
910 "class %s has interface %s as super class",
911 external_name(),
912 super_klass->external_name()
913 );
914 return false;
915 }
916
917 InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
918 ik_super->link_class_impl(CHECK_false);
919 }
920
921 // link all interfaces implemented by this class before linking this class
922 Array<InstanceKlass*>* interfaces = local_interfaces();
923 int num_interfaces = interfaces->length();
924 for (int index = 0; index < num_interfaces; index++) {
925 InstanceKlass* interk = interfaces->at(index);
926 interk->link_class_impl(CHECK_false);
927 }
928
929 // in case the class is linked in the process of linking its superclasses
930 if (is_linked()) {
931 return true;
932 }
933
934 // trace only the link time for this klass that includes
935 // the verification time
936 PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
937 ClassLoader::perf_class_link_selftime(),
938 ClassLoader::perf_classes_linked(),
939 jt->get_thread_stat()->perf_recursion_counts_addr(),
940 jt->get_thread_stat()->perf_timers_addr(),
941 PerfClassTraceTime::CLASS_LINK);
942
943 // verification & rewriting
944 {
945 HandleMark hm(THREAD);
946 Handle h_init_lock(THREAD, init_lock());
947 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
948 // rewritten will have been set if loader constraint error found
949 // on an earlier link attempt
950 // don't verify or rewrite if already rewritten
951 //
952
953 if (!is_linked()) {
954 if (!is_rewritten()) {
955 {
956 bool verify_ok = verify_code(THREAD);
957 if (!verify_ok) {
958 return false;
959 }
960 }
961
962 // Just in case a side-effect of verify linked this class already
963 // (which can sometimes happen since the verifier loads classes
964 // using custom class loaders, which are free to initialize things)
965 if (is_linked()) {
966 return true;
967 }
968
969 // also sets rewritten
970 rewrite_class(CHECK_false);
971 } else if (is_shared()) {
972 SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
973 }
974
975 // relocate jsrs and link methods after they are all rewritten
976 link_methods(CHECK_false);
977
978 // Initialize the vtable and interface table after
979 // methods have been rewritten since rewrite may
980 // fabricate new Method*s.
981 // also does loader constraint checking
982 //
983 // initialize_vtable and initialize_itable need to be rerun
984 // for a shared class if
985 // 1) the class is loaded by custom class loader or
986 // 2) the class is loaded by built-in class loader but failed to add archived loader constraints
987 bool need_init_table = true;
988 if (is_shared() && SystemDictionaryShared::check_linking_constraints(this, THREAD)) {
989 need_init_table = false;
990 }
991 if (need_init_table) {
992 vtable().initialize_vtable(true, CHECK_false);
993 itable().initialize_itable(true, CHECK_false);
994 }
995 #ifdef ASSERT
996 vtable().verify(tty, true);
997 // In case itable verification is ever added.
998 // itable().verify(tty, true);
999 #endif
1000 set_init_state(linked);
1001 if (JvmtiExport::should_post_class_prepare()) {
1002 Thread *thread = THREAD;
1003 assert(thread->is_Java_thread(), "thread->is_Java_thread()");
1004 JvmtiExport::post_class_prepare((JavaThread *) thread, this);
1005 }
1006 }
1007 }
1008 return true;
1009 }
1010
1011 // Rewrite the byte codes of all of the methods of a class.
1012 // The rewriter must be called exactly once. Rewriting must happen after
1013 // verification but before the first method of the class is executed.
1014 void InstanceKlass::rewrite_class(TRAPS) {
1015 assert(is_loaded(), "must be loaded");
1016 if (is_rewritten()) {
1017 assert(is_shared(), "rewriting an unshared class?");
1018 return;
1019 }
1020 Rewriter::rewrite(this, CHECK);
1021 set_rewritten();
1022 }
1023
1024 // Now relocate and link method entry points after class is rewritten.
1025 // This is outside is_rewritten flag. In case of an exception, it can be
1026 // executed more than once.
1027 void InstanceKlass::link_methods(TRAPS) {
1028 int len = methods()->length();
1029 for (int i = len-1; i >= 0; i--) {
1030 methodHandle m(THREAD, methods()->at(i));
1031
1032 // Set up method entry points for compiler and interpreter .
1033 m->link_method(m, CHECK);
1034 }
1035 }
1036
1037 // Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
1038 void InstanceKlass::initialize_super_interfaces(TRAPS) {
1039 assert (has_nonstatic_concrete_methods(), "caller should have checked this");
1040 for (int i = 0; i < local_interfaces()->length(); ++i) {
1041 InstanceKlass* ik = local_interfaces()->at(i);
1042
1043 // Initialization is depth first search ie. we start with top of the inheritance tree
1044 // has_nonstatic_concrete_methods drives searching superinterfaces since it
1045 // means has_nonstatic_concrete_methods in its superinterface hierarchy
1046 if (ik->has_nonstatic_concrete_methods()) {
1047 ik->initialize_super_interfaces(CHECK);
1048 }
1049
1050 // Only initialize() interfaces that "declare" concrete methods.
1051 if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
1052 ik->initialize(CHECK);
1053 }
1054 }
1055 }
1056
1057 void InstanceKlass::initialize_impl(TRAPS) {
1058 HandleMark hm(THREAD);
1059
1060 // Make sure klass is linked (verified) before initialization
1061 // A class could already be verified, since it has been reflected upon.
1062 link_class(CHECK);
1063
1064 DTRACE_CLASSINIT_PROBE(required, -1);
1065
1066 bool wait = false;
1067
1068 assert(THREAD->is_Java_thread(), "non-JavaThread in initialize_impl");
1069 JavaThread* jt = (JavaThread*)THREAD;
1070
1071 // refer to the JVM book page 47 for description of steps
1072 // Step 1
1073 {
1074 Handle h_init_lock(THREAD, init_lock());
1075 ObjectLocker ol(h_init_lock, THREAD, h_init_lock() != NULL);
1076
1077 // Step 2
1078 // If we were to use wait() instead of waitInterruptibly() then
1079 // we might end up throwing IE from link/symbol resolution sites
1080 // that aren't expected to throw. This would wreak havoc. See 6320309.
1081 while (is_being_initialized() && !is_reentrant_initialization(jt)) {
1082 wait = true;
1083 jt->set_class_to_be_initialized(this);
1084 ol.wait_uninterruptibly(jt);
1085 jt->set_class_to_be_initialized(NULL);
1086 }
1087
1088 // Step 3
1089 if (is_being_initialized() && is_reentrant_initialization(jt)) {
1090 DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
1091 return;
1092 }
1093
1094 // Step 4
1095 if (is_initialized()) {
1096 DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
1097 return;
1098 }
1099
1100 // Step 5
1101 if (is_in_error_state()) {
1102 DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
1103 ResourceMark rm(THREAD);
1104 const char* desc = "Could not initialize class ";
1105 const char* className = external_name();
1106 size_t msglen = strlen(desc) + strlen(className) + 1;
1107 char* message = NEW_RESOURCE_ARRAY(char, msglen);
1108 if (NULL == message) {
1109 // Out of memory: can't create detailed error message
1110 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), className);
1111 } else {
1112 jio_snprintf(message, msglen, "%s%s", desc, className);
1113 THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), message);
1114 }
1115 }
1116
1117 // Step 6
1118 set_init_state(being_initialized);
1119 set_init_thread(jt);
1120 }
1121
1122 // Step 7
1123 // Next, if C is a class rather than an interface, initialize it's super class and super
1124 // interfaces.
1125 if (!is_interface()) {
1126 Klass* super_klass = super();
1127 if (super_klass != NULL && super_klass->should_be_initialized()) {
1128 super_klass->initialize(THREAD);
1129 }
1130 // If C implements any interface that declares a non-static, concrete method,
1131 // the initialization of C triggers initialization of its super interfaces.
1132 // Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
1133 // having a superinterface that declares, non-static, concrete methods
1134 if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
1135 initialize_super_interfaces(THREAD);
1136 }
1137
1138 // If any exceptions, complete abruptly, throwing the same exception as above.
1139 if (HAS_PENDING_EXCEPTION) {
1140 Handle e(THREAD, PENDING_EXCEPTION);
1141 CLEAR_PENDING_EXCEPTION;
1142 {
1143 EXCEPTION_MARK;
1144 // Locks object, set state, and notify all waiting threads
1145 set_initialization_state_and_notify(initialization_error, THREAD);
1146 CLEAR_PENDING_EXCEPTION;
1147 }
1148 DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
1149 THROW_OOP(e());
1150 }
1151 }
1152
1153
1154 // Look for aot compiled methods for this klass, including class initializer.
1155 AOTLoader::load_for_klass(this, THREAD);
1156
1157 // Step 8
1158 {
1159 DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
1160 if (class_initializer() != NULL) {
1161 // Timer includes any side effects of class initialization (resolution,
1162 // etc), but not recursive entry into call_class_initializer().
1163 PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
1164 ClassLoader::perf_class_init_selftime(),
1165 ClassLoader::perf_classes_inited(),
1166 jt->get_thread_stat()->perf_recursion_counts_addr(),
1167 jt->get_thread_stat()->perf_timers_addr(),
1168 PerfClassTraceTime::CLASS_CLINIT);
1169 call_class_initializer(THREAD);
1170 } else {
1171 // The elapsed time is so small it's not worth counting.
1172 if (UsePerfData) {
1173 ClassLoader::perf_classes_inited()->inc();
1174 }
1175 call_class_initializer(THREAD);
1176 }
1177 }
1178
1179 // Step 9
1180 if (!HAS_PENDING_EXCEPTION) {
1181 set_initialization_state_and_notify(fully_initialized, CHECK);
1182 {
1183 debug_only(vtable().verify(tty, true);)
1184 }
1185 }
1186 else {
1187 // Step 10 and 11
1188 Handle e(THREAD, PENDING_EXCEPTION);
1189 CLEAR_PENDING_EXCEPTION;
1190 // JVMTI has already reported the pending exception
1191 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1192 JvmtiExport::clear_detected_exception(jt);
1193 {
1194 EXCEPTION_MARK;
1195 set_initialization_state_and_notify(initialization_error, THREAD);
1196 CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
1197 // JVMTI has already reported the pending exception
1198 // JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
1199 JvmtiExport::clear_detected_exception(jt);
1200 }
1201 DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
1202 if (e->is_a(SystemDictionary::Error_klass())) {
1203 THROW_OOP(e());
1204 } else {
1205 JavaCallArguments args(e);
1206 THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
1207 vmSymbols::throwable_void_signature(),
1208 &args);
1209 }
1210 }
1211 DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
1212 }
1213
1214
1215 void InstanceKlass::set_initialization_state_and_notify(ClassState state, TRAPS) {
1216 Handle h_init_lock(THREAD, init_lock());
1217 if (h_init_lock() != NULL) {
1218 ObjectLocker ol(h_init_lock, THREAD);
1219 set_init_thread(NULL); // reset _init_thread before changing _init_state
1220 set_init_state(state);
1221 fence_and_clear_init_lock();
1222 ol.notify_all(CHECK);
1223 } else {
1224 assert(h_init_lock() != NULL, "The initialization state should never be set twice");
1225 set_init_thread(NULL); // reset _init_thread before changing _init_state
1226 set_init_state(state);
1227 }
1228 }
1229
1230 Klass* InstanceKlass::implementor() const {
1231 Klass* volatile* k = adr_implementor();
1232 if (k == NULL) {
1233 return NULL;
1234 } else {
1235 // This load races with inserts, and therefore needs acquire.
1236 Klass* kls = Atomic::load_acquire(k);
1237 if (kls != NULL && !kls->is_loader_alive()) {
1238 return NULL; // don't return unloaded class
1239 } else {
1240 return kls;
1241 }
1242 }
1243 }
1244
1245
1246 void InstanceKlass::set_implementor(Klass* k) {
1247 assert_locked_or_safepoint(Compile_lock);
1248 assert(is_interface(), "not interface");
1249 Klass* volatile* addr = adr_implementor();
1250 assert(addr != NULL, "null addr");
1251 if (addr != NULL) {
1252 Atomic::release_store(addr, k);
1253 }
1254 }
1255
1256 int InstanceKlass::nof_implementors() const {
1257 Klass* k = implementor();
1258 if (k == NULL) {
1259 return 0;
1260 } else if (k != this) {
1261 return 1;
1262 } else {
1263 return 2;
1264 }
1265 }
1266
1267 // The embedded _implementor field can only record one implementor.
1268 // When there are more than one implementors, the _implementor field
1269 // is set to the interface Klass* itself. Following are the possible
1270 // values for the _implementor field:
1271 // NULL - no implementor
1272 // implementor Klass* - one implementor
1273 // self - more than one implementor
1274 //
1275 // The _implementor field only exists for interfaces.
1276 void InstanceKlass::add_implementor(Klass* k) {
1277 if (Universe::is_fully_initialized()) {
1278 assert_lock_strong(Compile_lock);
1279 }
1280 assert(is_interface(), "not interface");
1281 // Filter out my subinterfaces.
1282 // (Note: Interfaces are never on the subklass list.)
1283 if (InstanceKlass::cast(k)->is_interface()) return;
1284
1285 // Filter out subclasses whose supers already implement me.
1286 // (Note: CHA must walk subclasses of direct implementors
1287 // in order to locate indirect implementors.)
1288 Klass* sk = k->super();
1289 if (sk != NULL && InstanceKlass::cast(sk)->implements_interface(this))
1290 // We only need to check one immediate superclass, since the
1291 // implements_interface query looks at transitive_interfaces.
1292 // Any supers of the super have the same (or fewer) transitive_interfaces.
1293 return;
1294
1295 Klass* ik = implementor();
1296 if (ik == NULL) {
1297 set_implementor(k);
1298 } else if (ik != this && ik != k) {
1299 // There is already an implementor. Use itself as an indicator of
1300 // more than one implementors.
1301 set_implementor(this);
1302 }
1303
1304 // The implementor also implements the transitive_interfaces
1305 for (int index = 0; index < local_interfaces()->length(); index++) {
1306 InstanceKlass::cast(local_interfaces()->at(index))->add_implementor(k);
1307 }
1308 }
1309
1310 void InstanceKlass::init_implementor() {
1311 if (is_interface()) {
1312 set_implementor(NULL);
1313 }
1314 }
1315
1316
1317 void InstanceKlass::process_interfaces(Thread *thread) {
1318 // link this class into the implementors list of every interface it implements
1319 for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
1320 assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
1321 InstanceKlass* interf = InstanceKlass::cast(local_interfaces()->at(i));
1322 assert(interf->is_interface(), "expected interface");
1323 interf->add_implementor(this);
1324 }
1325 }
1326
1327 bool InstanceKlass::can_be_primary_super_slow() const {
1328 if (is_interface())
1329 return false;
1330 else
1331 return Klass::can_be_primary_super_slow();
1332 }
1333
1334 GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
1335 Array<InstanceKlass*>* transitive_interfaces) {
1336 // The secondaries are the implemented interfaces.
1337 Array<InstanceKlass*>* interfaces = transitive_interfaces;
1338 int num_secondaries = num_extra_slots + interfaces->length();
1339 if (num_secondaries == 0) {
1340 // Must share this for correct bootstrapping!
1341 set_secondary_supers(Universe::the_empty_klass_array());
1342 return NULL;
1343 } else if (num_extra_slots == 0) {
1344 // The secondary super list is exactly the same as the transitive interfaces, so
1345 // let's use it instead of making a copy.
1346 // Redefine classes has to be careful not to delete this!
1347 // We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
1348 // (but it's safe to do here because we won't write into _secondary_supers from this point on).
1349 set_secondary_supers((Array<Klass*>*)(address)interfaces);
1350 return NULL;
1351 } else {
1352 // Copy transitive interfaces to a temporary growable array to be constructed
1353 // into the secondary super list with extra slots.
1354 GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
1355 for (int i = 0; i < interfaces->length(); i++) {
1356 secondaries->push(interfaces->at(i));
1357 }
1358 return secondaries;
1359 }
1360 }
1361
1362 bool InstanceKlass::implements_interface(Klass* k) const {
1363 if (this == k) return true;
1364 assert(k->is_interface(), "should be an interface class");
1365 for (int i = 0; i < transitive_interfaces()->length(); i++) {
1366 if (transitive_interfaces()->at(i) == k) {
1367 return true;
1368 }
1369 }
1370 return false;
1371 }
1372
1373 bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
1374 // Verify direct super interface
1375 if (this == k) return true;
1376 assert(k->is_interface(), "should be an interface class");
1377 for (int i = 0; i < local_interfaces()->length(); i++) {
1378 if (local_interfaces()->at(i) == k) {
1379 return true;
1380 }
1381 }
1382 return false;
1383 }
1384
1385 objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
1386 check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
1387 int size = objArrayOopDesc::object_size(length);
1388 Klass* ak = array_klass(n, CHECK_NULL);
1389 objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
1390 /* do_zero */ true, CHECK_NULL);
1391 return o;
1392 }
1393
1394 instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
1395 if (TraceFinalizerRegistration) {
1396 tty->print("Registered ");
1397 i->print_value_on(tty);
1398 tty->print_cr(" (" INTPTR_FORMAT ") as finalizable", p2i(i));
1399 }
1400 instanceHandle h_i(THREAD, i);
1401 // Pass the handle as argument, JavaCalls::call expects oop as jobjects
1402 JavaValue result(T_VOID);
1403 JavaCallArguments args(h_i);
1404 methodHandle mh (THREAD, Universe::finalizer_register_method());
1405 JavaCalls::call(&result, mh, &args, CHECK_NULL);
1406 return h_i();
1407 }
1408
1409 instanceOop InstanceKlass::allocate_instance(TRAPS) {
1410 bool has_finalizer_flag = has_finalizer(); // Query before possible GC
1411 int size = size_helper(); // Query before forming handle.
1412
1413 instanceOop i;
1414
1415 i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
1416 if (has_finalizer_flag && !RegisterFinalizersAtInit) {
1417 i = register_finalizer(i, CHECK_NULL);
1418 }
1419 return i;
1420 }
1421
1422 instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
1423 return instanceHandle(THREAD, allocate_instance(THREAD));
1424 }
1425
1426 void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
1427 if (is_interface() || is_abstract()) {
1428 ResourceMark rm(THREAD);
1429 THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
1430 : vmSymbols::java_lang_InstantiationException(), external_name());
1431 }
1432 if (this == SystemDictionary::Class_klass()) {
1433 ResourceMark rm(THREAD);
1434 THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
1435 : vmSymbols::java_lang_IllegalAccessException(), external_name());
1436 }
1437 }
1438
1439 Klass* InstanceKlass::array_klass_impl(bool or_null, int n, TRAPS) {
1440 // Need load-acquire for lock-free read
1441 if (array_klasses_acquire() == NULL) {
1442 if (or_null) return NULL;
1443
1444 ResourceMark rm(THREAD);
1445 JavaThread *jt = (JavaThread *)THREAD;
1446 {
1447 // Atomic creation of array_klasses
1448 MutexLocker ma(THREAD, MultiArray_lock);
1449
1450 // Check if update has already taken place
1451 if (array_klasses() == NULL) {
1452 ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
1453 // use 'release' to pair with lock-free load
1454 release_set_array_klasses(k);
1455 }
1456 }
1457 }
1458 // _this will always be set at this point
1459 ObjArrayKlass* oak = array_klasses();
1460 if (or_null) {
1461 return oak->array_klass_or_null(n);
1462 }
1463 return oak->array_klass(n, THREAD);
1464 }
1465
1466 Klass* InstanceKlass::array_klass_impl(bool or_null, TRAPS) {
1467 return array_klass_impl(or_null, 1, THREAD);
1468 }
1469
1470 static int call_class_initializer_counter = 0; // for debugging
1471
1472 Method* InstanceKlass::class_initializer() const {
1473 Method* clinit = find_method(
1474 vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
1475 if (clinit != NULL && clinit->has_valid_initializer_flags()) {
1476 return clinit;
1477 }
1478 return NULL;
1479 }
1480
1481 void InstanceKlass::call_class_initializer(TRAPS) {
1482 if (ReplayCompiles &&
1483 (ReplaySuppressInitializers == 1 ||
1484 (ReplaySuppressInitializers >= 2 && class_loader() != NULL))) {
1485 // Hide the existence of the initializer for the purpose of replaying the compile
1486 return;
1487 }
1488
1489 methodHandle h_method(THREAD, class_initializer());
1490 assert(!is_initialized(), "we cannot initialize twice");
1491 LogTarget(Info, class, init) lt;
1492 if (lt.is_enabled()) {
1493 ResourceMark rm(THREAD);
1494 LogStream ls(lt);
1495 ls.print("%d Initializing ", call_class_initializer_counter++);
1496 name()->print_value_on(&ls);
1497 ls.print_cr("%s (" INTPTR_FORMAT ")", h_method() == NULL ? "(no method)" : "", p2i(this));
1498 }
1499 if (h_method() != NULL) {
1500 JavaCallArguments args; // No arguments
1501 JavaValue result(T_VOID);
1502 JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
1503 }
1504 }
1505
1506
1507 void InstanceKlass::mask_for(const methodHandle& method, int bci,
1508 InterpreterOopMap* entry_for) {
1509 // Lazily create the _oop_map_cache at first request
1510 // Lock-free access requires load_acquire.
1511 OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
1512 if (oop_map_cache == NULL) {
1513 MutexLocker x(OopMapCacheAlloc_lock);
1514 // Check if _oop_map_cache was allocated while we were waiting for this lock
1515 if ((oop_map_cache = _oop_map_cache) == NULL) {
1516 oop_map_cache = new OopMapCache();
1517 // Ensure _oop_map_cache is stable, since it is examined without a lock
1518 Atomic::release_store(&_oop_map_cache, oop_map_cache);
1519 }
1520 }
1521 // _oop_map_cache is constant after init; lookup below does its own locking.
1522 oop_map_cache->lookup(method, bci, entry_for);
1523 }
1524
1525 bool InstanceKlass::contains_field_offset(int offset) {
1526 fieldDescriptor fd;
1527 return find_field_from_offset(offset, false, &fd);
1528 }
1529
1530 bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1531 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1532 Symbol* f_name = fs.name();
1533 Symbol* f_sig = fs.signature();
1534 if (f_name == name && f_sig == sig) {
1535 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1536 return true;
1537 }
1538 }
1539 return false;
1540 }
1541
1542
1543 Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1544 const int n = local_interfaces()->length();
1545 for (int i = 0; i < n; i++) {
1546 Klass* intf1 = local_interfaces()->at(i);
1547 assert(intf1->is_interface(), "just checking type");
1548 // search for field in current interface
1549 if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
1550 assert(fd->is_static(), "interface field must be static");
1551 return intf1;
1552 }
1553 // search for field in direct superinterfaces
1554 Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
1555 if (intf2 != NULL) return intf2;
1556 }
1557 // otherwise field lookup fails
1558 return NULL;
1559 }
1560
1561
1562 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
1563 // search order according to newest JVM spec (5.4.3.2, p.167).
1564 // 1) search for field in current klass
1565 if (find_local_field(name, sig, fd)) {
1566 return const_cast<InstanceKlass*>(this);
1567 }
1568 // 2) search for field recursively in direct superinterfaces
1569 { Klass* intf = find_interface_field(name, sig, fd);
1570 if (intf != NULL) return intf;
1571 }
1572 // 3) apply field lookup recursively if superclass exists
1573 { Klass* supr = super();
1574 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
1575 }
1576 // 4) otherwise field lookup fails
1577 return NULL;
1578 }
1579
1580
1581 Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
1582 // search order according to newest JVM spec (5.4.3.2, p.167).
1583 // 1) search for field in current klass
1584 if (find_local_field(name, sig, fd)) {
1585 if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
1586 }
1587 // 2) search for field recursively in direct superinterfaces
1588 if (is_static) {
1589 Klass* intf = find_interface_field(name, sig, fd);
1590 if (intf != NULL) return intf;
1591 }
1592 // 3) apply field lookup recursively if superclass exists
1593 { Klass* supr = super();
1594 if (supr != NULL) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
1595 }
1596 // 4) otherwise field lookup fails
1597 return NULL;
1598 }
1599
1600
1601 bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1602 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1603 if (fs.offset() == offset) {
1604 fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
1605 if (fd->is_static() == is_static) return true;
1606 }
1607 }
1608 return false;
1609 }
1610
1611
1612 bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
1613 Klass* klass = const_cast<InstanceKlass*>(this);
1614 while (klass != NULL) {
1615 if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
1616 return true;
1617 }
1618 klass = klass->super();
1619 }
1620 return false;
1621 }
1622
1623
1624 void InstanceKlass::methods_do(void f(Method* method)) {
1625 // Methods aren't stable until they are loaded. This can be read outside
1626 // a lock through the ClassLoaderData for profiling
1627 if (!is_loaded()) {
1628 return;
1629 }
1630
1631 int len = methods()->length();
1632 for (int index = 0; index < len; index++) {
1633 Method* m = methods()->at(index);
1634 assert(m->is_method(), "must be method");
1635 f(m);
1636 }
1637 }
1638
1639
1640 void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
1641 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1642 if (fs.access_flags().is_static()) {
1643 fieldDescriptor& fd = fs.field_descriptor();
1644 cl->do_field(&fd);
1645 }
1646 }
1647 }
1648
1649
1650 void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
1651 for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
1652 if (fs.access_flags().is_static()) {
1653 fieldDescriptor& fd = fs.field_descriptor();
1654 f(&fd, mirror, CHECK);
1655 }
1656 }
1657 }
1658
1659
1660 static int compare_fields_by_offset(int* a, int* b) {
1661 return a[0] - b[0];
1662 }
1663
1664 void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
1665 InstanceKlass* super = superklass();
1666 if (super != NULL) {
1667 super->do_nonstatic_fields(cl);
1668 }
1669 fieldDescriptor fd;
1670 int length = java_fields_count();
1671 // In DebugInfo nonstatic fields are sorted by offset.
1672 int* fields_sorted = NEW_C_HEAP_ARRAY(int, 2*(length+1), mtClass);
1673 int j = 0;
1674 for (int i = 0; i < length; i += 1) {
1675 fd.reinitialize(this, i);
1676 if (!fd.is_static()) {
1677 fields_sorted[j + 0] = fd.offset();
1678 fields_sorted[j + 1] = i;
1679 j += 2;
1680 }
1681 }
1682 if (j > 0) {
1683 length = j;
1684 // _sort_Fn is defined in growableArray.hpp.
1685 qsort(fields_sorted, length/2, 2*sizeof(int), (_sort_Fn)compare_fields_by_offset);
1686 for (int i = 0; i < length; i += 2) {
1687 fd.reinitialize(this, fields_sorted[i + 1]);
1688 assert(!fd.is_static() && fd.offset() == fields_sorted[i], "only nonstatic fields");
1689 cl->do_field(&fd);
1690 }
1691 }
1692 FREE_C_HEAP_ARRAY(int, fields_sorted);
1693 }
1694
1695
1696 void InstanceKlass::array_klasses_do(void f(Klass* k, TRAPS), TRAPS) {
1697 if (array_klasses() != NULL)
1698 array_klasses()->array_klasses_do(f, THREAD);
1699 }
1700
1701 void InstanceKlass::array_klasses_do(void f(Klass* k)) {
1702 if (array_klasses() != NULL)
1703 array_klasses()->array_klasses_do(f);
1704 }
1705
1706 #ifdef ASSERT
1707 static int linear_search(const Array<Method*>* methods,
1708 const Symbol* name,
1709 const Symbol* signature) {
1710 const int len = methods->length();
1711 for (int index = 0; index < len; index++) {
1712 const Method* const m = methods->at(index);
1713 assert(m->is_method(), "must be method");
1714 if (m->signature() == signature && m->name() == name) {
1715 return index;
1716 }
1717 }
1718 return -1;
1719 }
1720 #endif
1721
1722 bool InstanceKlass::_disable_method_binary_search = false;
1723
1724 NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
1725 int len = methods->length();
1726 int l = 0;
1727 int h = len - 1;
1728 while (l <= h) {
1729 Method* m = methods->at(l);
1730 if (m->name() == name) {
1731 return l;
1732 }
1733 l++;
1734 }
1735 return -1;
1736 }
1737
1738 inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
1739 if (_disable_method_binary_search) {
1740 assert(DynamicDumpSharedSpaces, "must be");
1741 // At the final stage of dynamic dumping, the methods array may not be sorted
1742 // by ascending addresses of their names, so we can't use binary search anymore.
1743 // However, methods with the same name are still laid out consecutively inside the
1744 // methods array, so let's look for the first one that matches.
1745 return linear_search(methods, name);
1746 }
1747
1748 int len = methods->length();
1749 int l = 0;
1750 int h = len - 1;
1751
1752 // methods are sorted by ascending addresses of their names, so do binary search
1753 while (l <= h) {
1754 int mid = (l + h) >> 1;
1755 Method* m = methods->at(mid);
1756 assert(m->is_method(), "must be method");
1757 int res = m->name()->fast_compare(name);
1758 if (res == 0) {
1759 return mid;
1760 } else if (res < 0) {
1761 l = mid + 1;
1762 } else {
1763 h = mid - 1;
1764 }
1765 }
1766 return -1;
1767 }
1768
1769 // find_method looks up the name/signature in the local methods array
1770 Method* InstanceKlass::find_method(const Symbol* name,
1771 const Symbol* signature) const {
1772 return find_method_impl(name, signature,
1773 OverpassLookupMode::find,
1774 StaticLookupMode::find,
1775 PrivateLookupMode::find);
1776 }
1777
1778 Method* InstanceKlass::find_method_impl(const Symbol* name,
1779 const Symbol* signature,
1780 OverpassLookupMode overpass_mode,
1781 StaticLookupMode static_mode,
1782 PrivateLookupMode private_mode) const {
1783 return InstanceKlass::find_method_impl(methods(),
1784 name,
1785 signature,
1786 overpass_mode,
1787 static_mode,
1788 private_mode);
1789 }
1790
1791 // find_instance_method looks up the name/signature in the local methods array
1792 // and skips over static methods
1793 Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
1794 const Symbol* name,
1795 const Symbol* signature,
1796 PrivateLookupMode private_mode) {
1797 Method* const meth = InstanceKlass::find_method_impl(methods,
1798 name,
1799 signature,
1800 OverpassLookupMode::find,
1801 StaticLookupMode::skip,
1802 private_mode);
1803 assert(((meth == NULL) || !meth->is_static()),
1804 "find_instance_method should have skipped statics");
1805 return meth;
1806 }
1807
1808 // find_instance_method looks up the name/signature in the local methods array
1809 // and skips over static methods
1810 Method* InstanceKlass::find_instance_method(const Symbol* name,
1811 const Symbol* signature,
1812 PrivateLookupMode private_mode) const {
1813 return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
1814 }
1815
1816 // Find looks up the name/signature in the local methods array
1817 // and filters on the overpass, static and private flags
1818 // This returns the first one found
1819 // note that the local methods array can have up to one overpass, one static
1820 // and one instance (private or not) with the same name/signature
1821 Method* InstanceKlass::find_local_method(const Symbol* name,
1822 const Symbol* signature,
1823 OverpassLookupMode overpass_mode,
1824 StaticLookupMode static_mode,
1825 PrivateLookupMode private_mode) const {
1826 return InstanceKlass::find_method_impl(methods(),
1827 name,
1828 signature,
1829 overpass_mode,
1830 static_mode,
1831 private_mode);
1832 }
1833
1834 // Find looks up the name/signature in the local methods array
1835 // and filters on the overpass, static and private flags
1836 // This returns the first one found
1837 // note that the local methods array can have up to one overpass, one static
1838 // and one instance (private or not) with the same name/signature
1839 Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
1840 const Symbol* name,
1841 const Symbol* signature,
1842 OverpassLookupMode overpass_mode,
1843 StaticLookupMode static_mode,
1844 PrivateLookupMode private_mode) {
1845 return InstanceKlass::find_method_impl(methods,
1846 name,
1847 signature,
1848 overpass_mode,
1849 static_mode,
1850 private_mode);
1851 }
1852
1853 Method* InstanceKlass::find_method(const Array<Method*>* methods,
1854 const Symbol* name,
1855 const Symbol* signature) {
1856 return InstanceKlass::find_method_impl(methods,
1857 name,
1858 signature,
1859 OverpassLookupMode::find,
1860 StaticLookupMode::find,
1861 PrivateLookupMode::find);
1862 }
1863
1864 Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
1865 const Symbol* name,
1866 const Symbol* signature,
1867 OverpassLookupMode overpass_mode,
1868 StaticLookupMode static_mode,
1869 PrivateLookupMode private_mode) {
1870 int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
1871 return hit >= 0 ? methods->at(hit): NULL;
1872 }
1873
1874 // true if method matches signature and conforms to skipping_X conditions.
1875 static bool method_matches(const Method* m,
1876 const Symbol* signature,
1877 bool skipping_overpass,
1878 bool skipping_static,
1879 bool skipping_private) {
1880 return ((m->signature() == signature) &&
1881 (!skipping_overpass || !m->is_overpass()) &&
1882 (!skipping_static || !m->is_static()) &&
1883 (!skipping_private || !m->is_private()));
1884 }
1885
1886 // Used directly for default_methods to find the index into the
1887 // default_vtable_indices, and indirectly by find_method
1888 // find_method_index looks in the local methods array to return the index
1889 // of the matching name/signature. If, overpass methods are being ignored,
1890 // the search continues to find a potential non-overpass match. This capability
1891 // is important during method resolution to prefer a static method, for example,
1892 // over an overpass method.
1893 // There is the possibility in any _method's array to have the same name/signature
1894 // for a static method, an overpass method and a local instance method
1895 // To correctly catch a given method, the search criteria may need
1896 // to explicitly skip the other two. For local instance methods, it
1897 // is often necessary to skip private methods
1898 int InstanceKlass::find_method_index(const Array<Method*>* methods,
1899 const Symbol* name,
1900 const Symbol* signature,
1901 OverpassLookupMode overpass_mode,
1902 StaticLookupMode static_mode,
1903 PrivateLookupMode private_mode) {
1904 const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
1905 const bool skipping_static = (static_mode == StaticLookupMode::skip);
1906 const bool skipping_private = (private_mode == PrivateLookupMode::skip);
1907 const int hit = quick_search(methods, name);
1908 if (hit != -1) {
1909 const Method* const m = methods->at(hit);
1910
1911 // Do linear search to find matching signature. First, quick check
1912 // for common case, ignoring overpasses if requested.
1913 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1914 return hit;
1915 }
1916
1917 // search downwards through overloaded methods
1918 int i;
1919 for (i = hit - 1; i >= 0; --i) {
1920 const Method* const m = methods->at(i);
1921 assert(m->is_method(), "must be method");
1922 if (m->name() != name) {
1923 break;
1924 }
1925 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1926 return i;
1927 }
1928 }
1929 // search upwards
1930 for (i = hit + 1; i < methods->length(); ++i) {
1931 const Method* const m = methods->at(i);
1932 assert(m->is_method(), "must be method");
1933 if (m->name() != name) {
1934 break;
1935 }
1936 if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
1937 return i;
1938 }
1939 }
1940 // not found
1941 #ifdef ASSERT
1942 const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
1943 linear_search(methods, name, signature);
1944 assert(-1 == index, "binary search should have found entry %d", index);
1945 #endif
1946 }
1947 return -1;
1948 }
1949
1950 int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
1951 return find_method_by_name(methods(), name, end);
1952 }
1953
1954 int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
1955 const Symbol* name,
1956 int* end_ptr) {
1957 assert(end_ptr != NULL, "just checking");
1958 int start = quick_search(methods, name);
1959 int end = start + 1;
1960 if (start != -1) {
1961 while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
1962 while (end < methods->length() && (methods->at(end))->name() == name) ++end;
1963 *end_ptr = end;
1964 return start;
1965 }
1966 return -1;
1967 }
1968
1969 // uncached_lookup_method searches both the local class methods array and all
1970 // superclasses methods arrays, skipping any overpass methods in superclasses,
1971 // and possibly skipping private methods.
1972 Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
1973 const Symbol* signature,
1974 OverpassLookupMode overpass_mode,
1975 PrivateLookupMode private_mode) const {
1976 OverpassLookupMode overpass_local_mode = overpass_mode;
1977 const Klass* klass = this;
1978 while (klass != NULL) {
1979 Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
1980 signature,
1981 overpass_local_mode,
1982 StaticLookupMode::find,
1983 private_mode);
1984 if (method != NULL) {
1985 return method;
1986 }
1987 klass = klass->super();
1988 overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
1989 }
1990 return NULL;
1991 }
1992
1993 #ifdef ASSERT
1994 // search through class hierarchy and return true if this class or
1995 // one of the superclasses was redefined
1996 bool InstanceKlass::has_redefined_this_or_super() const {
1997 const Klass* klass = this;
1998 while (klass != NULL) {
1999 if (InstanceKlass::cast(klass)->has_been_redefined()) {
2000 return true;
2001 }
2002 klass = klass->super();
2003 }
2004 return false;
2005 }
2006 #endif
2007
2008 // lookup a method in the default methods list then in all transitive interfaces
2009 // Do NOT return private or static methods
2010 Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
2011 Symbol* signature) const {
2012 Method* m = NULL;
2013 if (default_methods() != NULL) {
2014 m = find_method(default_methods(), name, signature);
2015 }
2016 // Look up interfaces
2017 if (m == NULL) {
2018 m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
2019 }
2020 return m;
2021 }
2022
2023 // lookup a method in all the interfaces that this class implements
2024 // Do NOT return private or static methods, new in JDK8 which are not externally visible
2025 // They should only be found in the initial InterfaceMethodRef
2026 Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
2027 Symbol* signature,
2028 DefaultsLookupMode defaults_mode) const {
2029 Array<InstanceKlass*>* all_ifs = transitive_interfaces();
2030 int num_ifs = all_ifs->length();
2031 InstanceKlass *ik = NULL;
2032 for (int i = 0; i < num_ifs; i++) {
2033 ik = all_ifs->at(i);
2034 Method* m = ik->lookup_method(name, signature);
2035 if (m != NULL && m->is_public() && !m->is_static() &&
2036 ((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
2037 return m;
2038 }
2039 }
2040 return NULL;
2041 }
2042
2043 /* jni_id_for_impl for jfieldIds only */
2044 JNIid* InstanceKlass::jni_id_for_impl(int offset) {
2045 MutexLocker ml(JfieldIdCreation_lock);
2046 // Retry lookup after we got the lock
2047 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
2048 if (probe == NULL) {
2049 // Slow case, allocate new static field identifier
2050 probe = new JNIid(this, offset, jni_ids());
2051 set_jni_ids(probe);
2052 }
2053 return probe;
2054 }
2055
2056
2057 /* jni_id_for for jfieldIds only */
2058 JNIid* InstanceKlass::jni_id_for(int offset) {
2059 JNIid* probe = jni_ids() == NULL ? NULL : jni_ids()->find(offset);
2060 if (probe == NULL) {
2061 probe = jni_id_for_impl(offset);
2062 }
2063 return probe;
2064 }
2065
2066 u2 InstanceKlass::enclosing_method_data(int offset) const {
2067 const Array<jushort>* const inner_class_list = inner_classes();
2068 if (inner_class_list == NULL) {
2069 return 0;
2070 }
2071 const int length = inner_class_list->length();
2072 if (length % inner_class_next_offset == 0) {
2073 return 0;
2074 }
2075 const int index = length - enclosing_method_attribute_size;
2076 assert(offset < enclosing_method_attribute_size, "invalid offset");
2077 return inner_class_list->at(index + offset);
2078 }
2079
2080 void InstanceKlass::set_enclosing_method_indices(u2 class_index,
2081 u2 method_index) {
2082 Array<jushort>* inner_class_list = inner_classes();
2083 assert (inner_class_list != NULL, "_inner_classes list is not set up");
2084 int length = inner_class_list->length();
2085 if (length % inner_class_next_offset == enclosing_method_attribute_size) {
2086 int index = length - enclosing_method_attribute_size;
2087 inner_class_list->at_put(
2088 index + enclosing_method_class_index_offset, class_index);
2089 inner_class_list->at_put(
2090 index + enclosing_method_method_index_offset, method_index);
2091 }
2092 }
2093
2094 // Lookup or create a jmethodID.
2095 // This code is called by the VMThread and JavaThreads so the
2096 // locking has to be done very carefully to avoid deadlocks
2097 // and/or other cache consistency problems.
2098 //
2099 jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
2100 size_t idnum = (size_t)method_h->method_idnum();
2101 jmethodID* jmeths = methods_jmethod_ids_acquire();
2102 size_t length = 0;
2103 jmethodID id = NULL;
2104
2105 // We use a double-check locking idiom here because this cache is
2106 // performance sensitive. In the normal system, this cache only
2107 // transitions from NULL to non-NULL which is safe because we use
2108 // release_set_methods_jmethod_ids() to advertise the new cache.
2109 // A partially constructed cache should never be seen by a racing
2110 // thread. We also use release_store() to save a new jmethodID
2111 // in the cache so a partially constructed jmethodID should never be
2112 // seen either. Cache reads of existing jmethodIDs proceed without a
2113 // lock, but cache writes of a new jmethodID requires uniqueness and
2114 // creation of the cache itself requires no leaks so a lock is
2115 // generally acquired in those two cases.
2116 //
2117 // If the RedefineClasses() API has been used, then this cache can
2118 // grow and we'll have transitions from non-NULL to bigger non-NULL.
2119 // Cache creation requires no leaks and we require safety between all
2120 // cache accesses and freeing of the old cache so a lock is generally
2121 // acquired when the RedefineClasses() API has been used.
2122
2123 if (jmeths != NULL) {
2124 // the cache already exists
2125 if (!idnum_can_increment()) {
2126 // the cache can't grow so we can just get the current values
2127 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2128 } else {
2129 // cache can grow so we have to be more careful
2130 if (Threads::number_of_threads() == 0 ||
2131 SafepointSynchronize::is_at_safepoint()) {
2132 // we're single threaded or at a safepoint - no locking needed
2133 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2134 } else {
2135 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2136 get_jmethod_id_length_value(jmeths, idnum, &length, &id);
2137 }
2138 }
2139 }
2140 // implied else:
2141 // we need to allocate a cache so default length and id values are good
2142
2143 if (jmeths == NULL || // no cache yet
2144 length <= idnum || // cache is too short
2145 id == NULL) { // cache doesn't contain entry
2146
2147 // This function can be called by the VMThread so we have to do all
2148 // things that might block on a safepoint before grabbing the lock.
2149 // Otherwise, we can deadlock with the VMThread or have a cache
2150 // consistency issue. These vars keep track of what we might have
2151 // to free after the lock is dropped.
2152 jmethodID to_dealloc_id = NULL;
2153 jmethodID* to_dealloc_jmeths = NULL;
2154
2155 // may not allocate new_jmeths or use it if we allocate it
2156 jmethodID* new_jmeths = NULL;
2157 if (length <= idnum) {
2158 // allocate a new cache that might be used
2159 size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
2160 new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
2161 memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
2162 // cache size is stored in element[0], other elements offset by one
2163 new_jmeths[0] = (jmethodID)size;
2164 }
2165
2166 // allocate a new jmethodID that might be used
2167 jmethodID new_id = NULL;
2168 if (method_h->is_old() && !method_h->is_obsolete()) {
2169 // The method passed in is old (but not obsolete), we need to use the current version
2170 Method* current_method = method_with_idnum((int)idnum);
2171 assert(current_method != NULL, "old and but not obsolete, so should exist");
2172 new_id = Method::make_jmethod_id(class_loader_data(), current_method);
2173 } else {
2174 // It is the current version of the method or an obsolete method,
2175 // use the version passed in
2176 new_id = Method::make_jmethod_id(class_loader_data(), method_h());
2177 }
2178
2179 if (Threads::number_of_threads() == 0 ||
2180 SafepointSynchronize::is_at_safepoint()) {
2181 // we're single threaded or at a safepoint - no locking needed
2182 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2183 &to_dealloc_id, &to_dealloc_jmeths);
2184 } else {
2185 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2186 id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
2187 &to_dealloc_id, &to_dealloc_jmeths);
2188 }
2189
2190 // The lock has been dropped so we can free resources.
2191 // Free up either the old cache or the new cache if we allocated one.
2192 if (to_dealloc_jmeths != NULL) {
2193 FreeHeap(to_dealloc_jmeths);
2194 }
2195 // free up the new ID since it wasn't needed
2196 if (to_dealloc_id != NULL) {
2197 Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
2198 }
2199 }
2200 return id;
2201 }
2202
2203 // Figure out how many jmethodIDs haven't been allocated, and make
2204 // sure space for them is pre-allocated. This makes getting all
2205 // method ids much, much faster with classes with more than 8
2206 // methods, and has a *substantial* effect on performance with jvmti
2207 // code that loads all jmethodIDs for all classes.
2208 void InstanceKlass::ensure_space_for_methodids(int start_offset) {
2209 int new_jmeths = 0;
2210 int length = methods()->length();
2211 for (int index = start_offset; index < length; index++) {
2212 Method* m = methods()->at(index);
2213 jmethodID id = m->find_jmethod_id_or_null();
2214 if (id == NULL) {
2215 new_jmeths++;
2216 }
2217 }
2218 if (new_jmeths != 0) {
2219 Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
2220 }
2221 }
2222
2223 // Common code to fetch the jmethodID from the cache or update the
2224 // cache with the new jmethodID. This function should never do anything
2225 // that causes the caller to go to a safepoint or we can deadlock with
2226 // the VMThread or have cache consistency issues.
2227 //
2228 jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
2229 size_t idnum, jmethodID new_id,
2230 jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
2231 jmethodID** to_dealloc_jmeths_p) {
2232 assert(new_id != NULL, "sanity check");
2233 assert(to_dealloc_id_p != NULL, "sanity check");
2234 assert(to_dealloc_jmeths_p != NULL, "sanity check");
2235 assert(Threads::number_of_threads() == 0 ||
2236 SafepointSynchronize::is_at_safepoint() ||
2237 JmethodIdCreation_lock->owned_by_self(), "sanity check");
2238
2239 // reacquire the cache - we are locked, single threaded or at a safepoint
2240 jmethodID* jmeths = methods_jmethod_ids_acquire();
2241 jmethodID id = NULL;
2242 size_t length = 0;
2243
2244 if (jmeths == NULL || // no cache yet
2245 (length = (size_t)jmeths[0]) <= idnum) { // cache is too short
2246 if (jmeths != NULL) {
2247 // copy any existing entries from the old cache
2248 for (size_t index = 0; index < length; index++) {
2249 new_jmeths[index+1] = jmeths[index+1];
2250 }
2251 *to_dealloc_jmeths_p = jmeths; // save old cache for later delete
2252 }
2253 release_set_methods_jmethod_ids(jmeths = new_jmeths);
2254 } else {
2255 // fetch jmethodID (if any) from the existing cache
2256 id = jmeths[idnum+1];
2257 *to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
2258 }
2259 if (id == NULL) {
2260 // No matching jmethodID in the existing cache or we have a new
2261 // cache or we just grew the cache. This cache write is done here
2262 // by the first thread to win the foot race because a jmethodID
2263 // needs to be unique once it is generally available.
2264 id = new_id;
2265
2266 // The jmethodID cache can be read while unlocked so we have to
2267 // make sure the new jmethodID is complete before installing it
2268 // in the cache.
2269 Atomic::release_store(&jmeths[idnum+1], id);
2270 } else {
2271 *to_dealloc_id_p = new_id; // save new id for later delete
2272 }
2273 return id;
2274 }
2275
2276
2277 // Common code to get the jmethodID cache length and the jmethodID
2278 // value at index idnum if there is one.
2279 //
2280 void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
2281 size_t idnum, size_t *length_p, jmethodID* id_p) {
2282 assert(cache != NULL, "sanity check");
2283 assert(length_p != NULL, "sanity check");
2284 assert(id_p != NULL, "sanity check");
2285
2286 // cache size is stored in element[0], other elements offset by one
2287 *length_p = (size_t)cache[0];
2288 if (*length_p <= idnum) { // cache is too short
2289 *id_p = NULL;
2290 } else {
2291 *id_p = cache[idnum+1]; // fetch jmethodID (if any)
2292 }
2293 }
2294
2295
2296 // Lookup a jmethodID, NULL if not found. Do no blocking, no allocations, no handles
2297 jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
2298 size_t idnum = (size_t)method->method_idnum();
2299 jmethodID* jmeths = methods_jmethod_ids_acquire();
2300 size_t length; // length assigned as debugging crumb
2301 jmethodID id = NULL;
2302 if (jmeths != NULL && // If there is a cache
2303 (length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
2304 id = jmeths[idnum+1]; // Look up the id (may be NULL)
2305 }
2306 return id;
2307 }
2308
2309 inline DependencyContext InstanceKlass::dependencies() {
2310 DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
2311 return dep_context;
2312 }
2313
2314 int InstanceKlass::mark_dependent_nmethods(KlassDepChange& changes) {
2315 return dependencies().mark_dependent_nmethods(changes);
2316 }
2317
2318 void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
2319 dependencies().add_dependent_nmethod(nm);
2320 }
2321
2322 void InstanceKlass::remove_dependent_nmethod(nmethod* nm) {
2323 dependencies().remove_dependent_nmethod(nm);
2324 }
2325
2326 void InstanceKlass::clean_dependency_context() {
2327 dependencies().clean_unloading_dependents();
2328 }
2329
2330 #ifndef PRODUCT
2331 void InstanceKlass::print_dependent_nmethods(bool verbose) {
2332 dependencies().print_dependent_nmethods(verbose);
2333 }
2334
2335 bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
2336 return dependencies().is_dependent_nmethod(nm);
2337 }
2338 #endif //PRODUCT
2339
2340 void InstanceKlass::clean_weak_instanceklass_links() {
2341 clean_implementors_list();
2342 clean_method_data();
2343 }
2344
2345 void InstanceKlass::clean_implementors_list() {
2346 assert(is_loader_alive(), "this klass should be live");
2347 if (is_interface()) {
2348 assert (ClassUnloading, "only called for ClassUnloading");
2349 for (;;) {
2350 // Use load_acquire due to competing with inserts
2351 Klass* impl = Atomic::load_acquire(adr_implementor());
2352 if (impl != NULL && !impl->is_loader_alive()) {
2353 // NULL this field, might be an unloaded klass or NULL
2354 Klass* volatile* klass = adr_implementor();
2355 if (Atomic::cmpxchg(klass, impl, (Klass*)NULL) == impl) {
2356 // Successfully unlinking implementor.
2357 if (log_is_enabled(Trace, class, unload)) {
2358 ResourceMark rm;
2359 log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
2360 }
2361 return;
2362 }
2363 } else {
2364 return;
2365 }
2366 }
2367 }
2368 }
2369
2370 void InstanceKlass::clean_method_data() {
2371 for (int m = 0; m < methods()->length(); m++) {
2372 MethodData* mdo = methods()->at(m)->method_data();
2373 if (mdo != NULL) {
2374 MutexLocker ml(SafepointSynchronize::is_at_safepoint() ? NULL : mdo->extra_data_lock());
2375 mdo->clean_method_data(/*always_clean*/false);
2376 }
2377 }
2378 }
2379
2380 bool InstanceKlass::supers_have_passed_fingerprint_checks() {
2381 if (java_super() != NULL && !java_super()->has_passed_fingerprint_check()) {
2382 ResourceMark rm;
2383 log_trace(class, fingerprint)("%s : super %s not fingerprinted", external_name(), java_super()->external_name());
2384 return false;
2385 }
2386
2387 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
2388 if (local_interfaces != NULL) {
2389 int length = local_interfaces->length();
2390 for (int i = 0; i < length; i++) {
2391 InstanceKlass* intf = local_interfaces->at(i);
2392 if (!intf->has_passed_fingerprint_check()) {
2393 ResourceMark rm;
2394 log_trace(class, fingerprint)("%s : interface %s not fingerprinted", external_name(), intf->external_name());
2395 return false;
2396 }
2397 }
2398 }
2399
2400 return true;
2401 }
2402
2403 bool InstanceKlass::should_store_fingerprint(bool is_hidden_or_anonymous) {
2404 #if INCLUDE_AOT
2405 // We store the fingerprint into the InstanceKlass only in the following 2 cases:
2406 if (CalculateClassFingerprint) {
2407 // (1) We are running AOT to generate a shared library.
2408 return true;
2409 }
2410 if (Arguments::is_dumping_archive()) {
2411 // (2) We are running -Xshare:dump or -XX:ArchiveClassesAtExit to create a shared archive
2412 return true;
2413 }
2414 if (UseAOT && is_hidden_or_anonymous) {
2415 // (3) We are using AOT code from a shared library and see a hidden or unsafe anonymous class
2416 return true;
2417 }
2418 #endif
2419
2420 // In all other cases we might set the _misc_has_passed_fingerprint_check bit,
2421 // but do not store the 64-bit fingerprint to save space.
2422 return false;
2423 }
2424
2425 bool InstanceKlass::has_stored_fingerprint() const {
2426 #if INCLUDE_AOT
2427 return should_store_fingerprint() || is_shared();
2428 #else
2429 return false;
2430 #endif
2431 }
2432
2433 uint64_t InstanceKlass::get_stored_fingerprint() const {
2434 address adr = adr_fingerprint();
2435 if (adr != NULL) {
2436 return (uint64_t)Bytes::get_native_u8(adr); // adr may not be 64-bit aligned
2437 }
2438 return 0;
2439 }
2440
2441 void InstanceKlass::store_fingerprint(uint64_t fingerprint) {
2442 address adr = adr_fingerprint();
2443 if (adr != NULL) {
2444 Bytes::put_native_u8(adr, (u8)fingerprint); // adr may not be 64-bit aligned
2445
2446 ResourceMark rm;
2447 log_trace(class, fingerprint)("stored as " PTR64_FORMAT " for class %s", fingerprint, external_name());
2448 }
2449 }
2450
2451 void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
2452 Klass::metaspace_pointers_do(it);
2453
2454 if (log_is_enabled(Trace, cds)) {
2455 ResourceMark rm;
2456 log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
2457 }
2458
2459 it->push(&_annotations);
2460 it->push((Klass**)&_array_klasses);
2461 it->push(&_constants);
2462 it->push(&_inner_classes);
2463 #if INCLUDE_JVMTI
2464 it->push(&_previous_versions);
2465 #endif
2466 it->push(&_methods);
2467 it->push(&_default_methods);
2468 it->push(&_local_interfaces);
2469 it->push(&_transitive_interfaces);
2470 it->push(&_method_ordering);
2471 it->push(&_default_vtable_indices);
2472 it->push(&_fields);
2473
2474 if (itable_length() > 0) {
2475 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
2476 int method_table_offset_in_words = ioe->offset()/wordSize;
2477 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
2478 / itableOffsetEntry::size();
2479
2480 for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
2481 if (ioe->interface_klass() != NULL) {
2482 it->push(ioe->interface_klass_addr());
2483 itableMethodEntry* ime = ioe->first_method_entry(this);
2484 int n = klassItable::method_count_for_interface(ioe->interface_klass());
2485 for (int index = 0; index < n; index ++) {
2486 it->push(ime[index].method_addr());
2487 }
2488 }
2489 }
2490 }
2491
2492 it->push(&_nest_members);
2493 it->push(&_permitted_subclasses);
2494 it->push(&_record_components);
2495 }
2496
2497 void InstanceKlass::remove_unshareable_info() {
2498 Klass::remove_unshareable_info();
2499
2500 if (SystemDictionaryShared::has_class_failed_verification(this)) {
2501 // Classes are attempted to link during dumping and may fail,
2502 // but these classes are still in the dictionary and class list in CLD.
2503 // If the class has failed verification, there is nothing else to remove.
2504 return;
2505 }
2506
2507 // Reset to the 'allocated' state to prevent any premature accessing to
2508 // a shared class at runtime while the class is still being loaded and
2509 // restored. A class' init_state is set to 'loaded' at runtime when it's
2510 // being added to class hierarchy (see SystemDictionary:::add_to_hierarchy()).
2511 _init_state = allocated;
2512
2513 { // Otherwise this needs to take out the Compile_lock.
2514 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
2515 init_implementor();
2516 }
2517
2518 constants()->remove_unshareable_info();
2519
2520 for (int i = 0; i < methods()->length(); i++) {
2521 Method* m = methods()->at(i);
2522 m->remove_unshareable_info();
2523 }
2524
2525 // do array classes also.
2526 if (array_klasses() != NULL) {
2527 array_klasses()->remove_unshareable_info();
2528 }
2529
2530 // These are not allocated from metaspace. They are safe to set to NULL.
2531 _source_debug_extension = NULL;
2532 _dep_context = NULL;
2533 _osr_nmethods_head = NULL;
2534 #if INCLUDE_JVMTI
2535 _breakpoints = NULL;
2536 _previous_versions = NULL;
2537 _cached_class_file = NULL;
2538 _jvmti_cached_class_field_map = NULL;
2539 #endif
2540
2541 _init_thread = NULL;
2542 _methods_jmethod_ids = NULL;
2543 _jni_ids = NULL;
2544 _oop_map_cache = NULL;
2545 // clear _nest_host to ensure re-load at runtime
2546 _nest_host = NULL;
2547 _package_entry = NULL;
2548 _dep_context_last_cleaned = 0;
2549 }
2550
2551 void InstanceKlass::remove_java_mirror() {
2552 Klass::remove_java_mirror();
2553
2554 // do array classes also.
2555 if (array_klasses() != NULL) {
2556 array_klasses()->remove_java_mirror();
2557 }
2558 }
2559
2560 void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
2561 PackageEntry* pkg_entry, TRAPS) {
2562 // SystemDictionary::add_to_hierarchy() sets the init_state to loaded
2563 // before the InstanceKlass is added to the SystemDictionary. Make
2564 // sure the current state is <loaded.
2565 assert(!is_loaded(), "invalid init state");
2566 set_package(loader_data, pkg_entry, CHECK);
2567 Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
2568
2569 Array<Method*>* methods = this->methods();
2570 int num_methods = methods->length();
2571 for (int index = 0; index < num_methods; ++index) {
2572 methods->at(index)->restore_unshareable_info(CHECK);
2573 }
2574 if (JvmtiExport::has_redefined_a_class()) {
2575 // Reinitialize vtable because RedefineClasses may have changed some
2576 // entries in this vtable for super classes so the CDS vtable might
2577 // point to old or obsolete entries. RedefineClasses doesn't fix up
2578 // vtables in the shared system dictionary, only the main one.
2579 // It also redefines the itable too so fix that too.
2580 vtable().initialize_vtable(false, CHECK);
2581 itable().initialize_itable(false, CHECK);
2582 }
2583
2584 // restore constant pool resolved references
2585 constants()->restore_unshareable_info(CHECK);
2586
2587 if (array_klasses() != NULL) {
2588 // Array classes have null protection domain.
2589 // --> see ArrayKlass::complete_create_array_klass()
2590 array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
2591 }
2592
2593 // Initialize current biased locking state.
2594 if (UseBiasedLocking && BiasedLocking::enabled()) {
2595 set_prototype_header(markWord::biased_locking_prototype());
2596 }
2597 }
2598
2599 void InstanceKlass::set_shared_class_loader_type(s2 loader_type) {
2600 switch (loader_type) {
2601 case ClassLoader::BOOT_LOADER:
2602 _misc_flags |= _misc_is_shared_boot_class;
2603 break;
2604 case ClassLoader::PLATFORM_LOADER:
2605 _misc_flags |= _misc_is_shared_platform_class;
2606 break;
2607 case ClassLoader::APP_LOADER:
2608 _misc_flags |= _misc_is_shared_app_class;
2609 break;
2610 default:
2611 ShouldNotReachHere();
2612 break;
2613 }
2614 }
2615
2616 void InstanceKlass::assign_class_loader_type() {
2617 ClassLoaderData *cld = class_loader_data();
2618 if (cld->is_boot_class_loader_data()) {
2619 set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
2620 }
2621 else if (cld->is_platform_class_loader_data()) {
2622 set_shared_class_loader_type(ClassLoader::PLATFORM_LOADER);
2623 }
2624 else if (cld->is_system_class_loader_data()) {
2625 set_shared_class_loader_type(ClassLoader::APP_LOADER);
2626 }
2627 }
2628
2629 #if INCLUDE_JVMTI
2630 static void clear_all_breakpoints(Method* m) {
2631 m->clear_all_breakpoints();
2632 }
2633 #endif
2634
2635 void InstanceKlass::unload_class(InstanceKlass* ik) {
2636 // Release dependencies.
2637 ik->dependencies().remove_all_dependents();
2638
2639 // notify the debugger
2640 if (JvmtiExport::should_post_class_unload()) {
2641 JvmtiExport::post_class_unload(ik);
2642 }
2643
2644 // notify ClassLoadingService of class unload
2645 ClassLoadingService::notify_class_unloaded(ik);
2646
2647 if (Arguments::is_dumping_archive()) {
2648 SystemDictionaryShared::remove_dumptime_info(ik);
2649 }
2650
2651 if (log_is_enabled(Info, class, unload)) {
2652 ResourceMark rm;
2653 log_info(class, unload)("unloading class %s " INTPTR_FORMAT, ik->external_name(), p2i(ik));
2654 }
2655
2656 Events::log_class_unloading(Thread::current(), ik);
2657
2658 #if INCLUDE_JFR
2659 assert(ik != NULL, "invariant");
2660 EventClassUnload event;
2661 event.set_unloadedClass(ik);
2662 event.set_definingClassLoader(ik->class_loader_data());
2663 event.commit();
2664 #endif
2665 }
2666
2667 static void method_release_C_heap_structures(Method* m) {
2668 m->release_C_heap_structures();
2669 }
2670
2671 void InstanceKlass::release_C_heap_structures() {
2672
2673 // Clean up C heap
2674 release_C_heap_structures_internal();
2675 constants()->release_C_heap_structures();
2676
2677 // Deallocate and call destructors for MDO mutexes
2678 methods_do(method_release_C_heap_structures);
2679 }
2680
2681 void InstanceKlass::release_C_heap_structures_internal() {
2682 Klass::release_C_heap_structures();
2683
2684 // Can't release the constant pool here because the constant pool can be
2685 // deallocated separately from the InstanceKlass for default methods and
2686 // redefine classes.
2687
2688 // Deallocate oop map cache
2689 if (_oop_map_cache != NULL) {
2690 delete _oop_map_cache;
2691 _oop_map_cache = NULL;
2692 }
2693
2694 // Deallocate JNI identifiers for jfieldIDs
2695 JNIid::deallocate(jni_ids());
2696 set_jni_ids(NULL);
2697
2698 jmethodID* jmeths = methods_jmethod_ids_acquire();
2699 if (jmeths != (jmethodID*)NULL) {
2700 release_set_methods_jmethod_ids(NULL);
2701 FreeHeap(jmeths);
2702 }
2703
2704 assert(_dep_context == NULL,
2705 "dependencies should already be cleaned");
2706
2707 #if INCLUDE_JVMTI
2708 // Deallocate breakpoint records
2709 if (breakpoints() != 0x0) {
2710 methods_do(clear_all_breakpoints);
2711 assert(breakpoints() == 0x0, "should have cleared breakpoints");
2712 }
2713
2714 // deallocate the cached class file
2715 if (_cached_class_file != NULL) {
2716 os::free(_cached_class_file);
2717 _cached_class_file = NULL;
2718 }
2719 #endif
2720
2721 FREE_C_HEAP_ARRAY(char, _source_debug_extension);
2722 }
2723
2724 void InstanceKlass::set_source_debug_extension(const char* array, int length) {
2725 if (array == NULL) {
2726 _source_debug_extension = NULL;
2727 } else {
2728 // Adding one to the attribute length in order to store a null terminator
2729 // character could cause an overflow because the attribute length is
2730 // already coded with an u4 in the classfile, but in practice, it's
2731 // unlikely to happen.
2732 assert((length+1) > length, "Overflow checking");
2733 char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
2734 for (int i = 0; i < length; i++) {
2735 sde[i] = array[i];
2736 }
2737 sde[length] = '\0';
2738 _source_debug_extension = sde;
2739 }
2740 }
2741
2742 const char* InstanceKlass::signature_name() const {
2743 int hash_len = 0;
2744 char hash_buf[40];
2745
2746 // If this is an unsafe anonymous class, append a hash to make the name unique
2747 if (is_unsafe_anonymous()) {
2748 intptr_t hash = (java_mirror() != NULL) ? java_mirror()->identity_hash() : 0;
2749 jio_snprintf(hash_buf, sizeof(hash_buf), "/" UINTX_FORMAT, (uintx)hash);
2750 hash_len = (int)strlen(hash_buf);
2751 }
2752
2753 // Get the internal name as a c string
2754 const char* src = (const char*) (name()->as_C_string());
2755 const int src_length = (int)strlen(src);
2756
2757 char* dest = NEW_RESOURCE_ARRAY(char, src_length + hash_len + 3);
2758
2759 // Add L as type indicator
2760 int dest_index = 0;
2761 dest[dest_index++] = JVM_SIGNATURE_CLASS;
2762
2763 // Add the actual class name
2764 for (int src_index = 0; src_index < src_length; ) {
2765 dest[dest_index++] = src[src_index++];
2766 }
2767
2768 if (is_hidden()) { // Replace the last '+' with a '.'.
2769 for (int index = (int)src_length; index > 0; index--) {
2770 if (dest[index] == '+') {
2771 dest[index] = JVM_SIGNATURE_DOT;
2772 break;
2773 }
2774 }
2775 }
2776
2777 // If we have a hash, append it
2778 for (int hash_index = 0; hash_index < hash_len; ) {
2779 dest[dest_index++] = hash_buf[hash_index++];
2780 }
2781
2782 // Add the semicolon and the NULL
2783 dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
2784 dest[dest_index] = '\0';
2785 return dest;
2786 }
2787
2788 ModuleEntry* InstanceKlass::module() const {
2789 // For an unsafe anonymous class return the host class' module
2790 if (is_unsafe_anonymous()) {
2791 assert(unsafe_anonymous_host() != NULL, "unsafe anonymous class must have a host class");
2792 return unsafe_anonymous_host()->module();
2793 }
2794
2795 if (is_hidden() &&
2796 in_unnamed_package() &&
2797 class_loader_data()->has_class_mirror_holder()) {
2798 // For a non-strong hidden class defined to an unnamed package,
2799 // its (class held) CLD will not have an unnamed module created for it.
2800 // Two choices to find the correct ModuleEntry:
2801 // 1. If hidden class is within a nest, use nest host's module
2802 // 2. Find the unnamed module off from the class loader
2803 // For now option #2 is used since a nest host is not set until
2804 // after the instance class is created in jvm_lookup_define_class().
2805 if (class_loader_data()->is_boot_class_loader_data()) {
2806 return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
2807 } else {
2808 oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
2809 assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
2810 return java_lang_Module::module_entry(module);
2811 }
2812 }
2813
2814 // Class is in a named package
2815 if (!in_unnamed_package()) {
2816 return _package_entry->module();
2817 }
2818
2819 // Class is in an unnamed package, return its loader's unnamed module
2820 return class_loader_data()->unnamed_module();
2821 }
2822
2823 void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
2824
2825 // ensure java/ packages only loaded by boot or platform builtin loaders
2826 // not needed for shared class since CDS does not archive prohibited classes.
2827 if (!is_shared()) {
2828 check_prohibited_package(name(), loader_data, CHECK);
2829 }
2830
2831 // ClassLoader::package_from_class_name has already incremented the refcount of the symbol
2832 // it returns, so we need to decrement it when the current function exits.
2833 TempNewSymbol from_class_name =
2834 (pkg_entry != NULL) ? NULL : ClassLoader::package_from_class_name(name());
2835
2836 Symbol* pkg_name;
2837 if (pkg_entry != NULL) {
2838 pkg_name = pkg_entry->name();
2839 } else {
2840 pkg_name = from_class_name;
2841 }
2842
2843 if (pkg_name != NULL && loader_data != NULL) {
2844
2845 // Find in class loader's package entry table.
2846 _package_entry = pkg_entry != NULL ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
2847
2848 // If the package name is not found in the loader's package
2849 // entry table, it is an indication that the package has not
2850 // been defined. Consider it defined within the unnamed module.
2851 if (_package_entry == NULL) {
2852
2853 if (!ModuleEntryTable::javabase_defined()) {
2854 // Before java.base is defined during bootstrapping, define all packages in
2855 // the java.base module. If a non-java.base package is erroneously placed
2856 // in the java.base module it will be caught later when java.base
2857 // is defined by ModuleEntryTable::verify_javabase_packages check.
2858 assert(ModuleEntryTable::javabase_moduleEntry() != NULL, JAVA_BASE_NAME " module is NULL");
2859 _package_entry = loader_data->packages()->lookup(pkg_name, ModuleEntryTable::javabase_moduleEntry());
2860 } else {
2861 assert(loader_data->unnamed_module() != NULL, "unnamed module is NULL");
2862 _package_entry = loader_data->packages()->lookup(pkg_name,
2863 loader_data->unnamed_module());
2864 }
2865
2866 // A package should have been successfully created
2867 DEBUG_ONLY(ResourceMark rm(THREAD));
2868 assert(_package_entry != NULL, "Package entry for class %s not found, loader %s",
2869 name()->as_C_string(), loader_data->loader_name_and_id());
2870 }
2871
2872 if (log_is_enabled(Debug, module)) {
2873 ResourceMark rm(THREAD);
2874 ModuleEntry* m = _package_entry->module();
2875 log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
2876 external_name(),
2877 pkg_name->as_C_string(),
2878 loader_data->loader_name_and_id(),
2879 (m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
2880 }
2881 } else {
2882 ResourceMark rm(THREAD);
2883 log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
2884 external_name(),
2885 (loader_data != NULL) ? loader_data->loader_name_and_id() : "NULL",
2886 UNNAMED_MODULE);
2887 }
2888 }
2889
2890 // Function set_classpath_index checks if the package of the InstanceKlass is in the
2891 // boot loader's package entry table. If so, then it sets the classpath_index
2892 // in the package entry record.
2893 //
2894 // The classpath_index field is used to find the entry on the boot loader class
2895 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
2896 // in an unnamed module. It is also used to indicate (for all packages whose
2897 // classes are loaded by the boot loader) that at least one of the package's
2898 // classes has been loaded.
2899 void InstanceKlass::set_classpath_index(s2 path_index, TRAPS) {
2900 if (_package_entry != NULL) {
2901 DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
2902 assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
2903 assert(path_index != -1, "Unexpected classpath_index");
2904 _package_entry->set_classpath_index(path_index);
2905 }
2906 }
2907
2908 // different versions of is_same_class_package
2909
2910 bool InstanceKlass::is_same_class_package(const Klass* class2) const {
2911 oop classloader1 = this->class_loader();
2912 PackageEntry* classpkg1 = this->package();
2913 if (class2->is_objArray_klass()) {
2914 class2 = ObjArrayKlass::cast(class2)->bottom_klass();
2915 }
2916
2917 oop classloader2;
2918 PackageEntry* classpkg2;
2919 if (class2->is_instance_klass()) {
2920 classloader2 = class2->class_loader();
2921 classpkg2 = class2->package();
2922 } else {
2923 assert(class2->is_typeArray_klass(), "should be type array");
2924 classloader2 = NULL;
2925 classpkg2 = NULL;
2926 }
2927
2928 // Same package is determined by comparing class loader
2929 // and package entries. Both must be the same. This rule
2930 // applies even to classes that are defined in the unnamed
2931 // package, they still must have the same class loader.
2932 if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
2933 return true;
2934 }
2935
2936 return false;
2937 }
2938
2939 // return true if this class and other_class are in the same package. Classloader
2940 // and classname information is enough to determine a class's package
2941 bool InstanceKlass::is_same_class_package(oop other_class_loader,
2942 const Symbol* other_class_name) const {
2943 if (class_loader() != other_class_loader) {
2944 return false;
2945 }
2946 if (name()->fast_compare(other_class_name) == 0) {
2947 return true;
2948 }
2949
2950 {
2951 ResourceMark rm;
2952
2953 bool bad_class_name = false;
2954 TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
2955 if (bad_class_name) {
2956 return false;
2957 }
2958 // Check that package_from_class_name() returns NULL, not "", if there is no package.
2959 assert(other_pkg == NULL || other_pkg->utf8_length() > 0, "package name is empty string");
2960
2961 const Symbol* const this_package_name =
2962 this->package() != NULL ? this->package()->name() : NULL;
2963
2964 if (this_package_name == NULL || other_pkg == NULL) {
2965 // One of the two doesn't have a package. Only return true if the other
2966 // one also doesn't have a package.
2967 return this_package_name == other_pkg;
2968 }
2969
2970 // Check if package is identical
2971 return this_package_name->fast_compare(other_pkg) == 0;
2972 }
2973 }
2974
2975 // Returns true iff super_method can be overridden by a method in targetclassname
2976 // See JLS 3rd edition 8.4.6.1
2977 // Assumes name-signature match
2978 // "this" is InstanceKlass of super_method which must exist
2979 // note that the InstanceKlass of the method in the targetclassname has not always been created yet
2980 bool InstanceKlass::is_override(const methodHandle& super_method, Handle targetclassloader, Symbol* targetclassname, TRAPS) {
2981 // Private methods can not be overridden
2982 if (super_method->is_private()) {
2983 return false;
2984 }
2985 // If super method is accessible, then override
2986 if ((super_method->is_protected()) ||
2987 (super_method->is_public())) {
2988 return true;
2989 }
2990 // Package-private methods are not inherited outside of package
2991 assert(super_method->is_package_private(), "must be package private");
2992 return(is_same_class_package(targetclassloader(), targetclassname));
2993 }
2994
2995 // Only boot and platform class loaders can define classes in "java/" packages.
2996 void InstanceKlass::check_prohibited_package(Symbol* class_name,
2997 ClassLoaderData* loader_data,
2998 TRAPS) {
2999 if (!loader_data->is_boot_class_loader_data() &&
3000 !loader_data->is_platform_class_loader_data() &&
3001 class_name != NULL) {
3002 ResourceMark rm(THREAD);
3003 char* name = class_name->as_C_string();
3004 if (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/') {
3005 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
3006 assert(pkg_name != NULL, "Error in parsing package name starting with 'java/'");
3007 name = pkg_name->as_C_string();
3008 const char* class_loader_name = loader_data->loader_name_and_id();
3009 StringUtils::replace_no_expand(name, "/", ".");
3010 const char* msg_text1 = "Class loader (instance of): ";
3011 const char* msg_text2 = " tried to load prohibited package name: ";
3012 size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
3013 char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
3014 jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
3015 THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
3016 }
3017 }
3018 return;
3019 }
3020
3021 bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
3022 constantPoolHandle i_cp(THREAD, constants());
3023 for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
3024 int ioff = iter.inner_class_info_index();
3025 if (ioff != 0) {
3026 // Check to see if the name matches the class we're looking for
3027 // before attempting to find the class.
3028 if (i_cp->klass_name_at_matches(this, ioff)) {
3029 Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
3030 if (this == inner_klass) {
3031 *ooff = iter.outer_class_info_index();
3032 *noff = iter.inner_name_index();
3033 return true;
3034 }
3035 }
3036 }
3037 }
3038 return false;
3039 }
3040
3041 InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
3042 InstanceKlass* outer_klass = NULL;
3043 *inner_is_member = false;
3044 int ooff = 0, noff = 0;
3045 bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
3046 if (has_inner_classes_attr) {
3047 constantPoolHandle i_cp(THREAD, constants());
3048 if (ooff != 0) {
3049 Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
3050 outer_klass = InstanceKlass::cast(ok);
3051 *inner_is_member = true;
3052 }
3053 if (NULL == outer_klass) {
3054 // It may be a local or anonymous class; try for that.
3055 int encl_method_class_idx = enclosing_method_class_index();
3056 if (encl_method_class_idx != 0) {
3057 Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
3058 outer_klass = InstanceKlass::cast(ok);
3059 *inner_is_member = false;
3060 }
3061 }
3062 }
3063
3064 // If no inner class attribute found for this class.
3065 if (NULL == outer_klass) return NULL;
3066
3067 // Throws an exception if outer klass has not declared k as an inner klass
3068 // We need evidence that each klass knows about the other, or else
3069 // the system could allow a spoof of an inner class to gain access rights.
3070 Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
3071 return outer_klass;
3072 }
3073
3074 jint InstanceKlass::compute_modifier_flags(TRAPS) const {
3075 jint access = access_flags().as_int();
3076
3077 // But check if it happens to be member class.
3078 InnerClassesIterator iter(this);
3079 for (; !iter.done(); iter.next()) {
3080 int ioff = iter.inner_class_info_index();
3081 // Inner class attribute can be zero, skip it.
3082 // Strange but true: JVM spec. allows null inner class refs.
3083 if (ioff == 0) continue;
3084
3085 // only look at classes that are already loaded
3086 // since we are looking for the flags for our self.
3087 Symbol* inner_name = constants()->klass_name_at(ioff);
3088 if (name() == inner_name) {
3089 // This is really a member class.
3090 access = iter.inner_access_flags();
3091 break;
3092 }
3093 }
3094 // Remember to strip ACC_SUPER bit
3095 return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
3096 }
3097
3098 jint InstanceKlass::jvmti_class_status() const {
3099 jint result = 0;
3100
3101 if (is_linked()) {
3102 result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
3103 }
3104
3105 if (is_initialized()) {
3106 assert(is_linked(), "Class status is not consistent");
3107 result |= JVMTI_CLASS_STATUS_INITIALIZED;
3108 }
3109 if (is_in_error_state()) {
3110 result |= JVMTI_CLASS_STATUS_ERROR;
3111 }
3112 return result;
3113 }
3114
3115 Method* InstanceKlass::method_at_itable(Klass* holder, int index, TRAPS) {
3116 itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
3117 int method_table_offset_in_words = ioe->offset()/wordSize;
3118 int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words())
3119 / itableOffsetEntry::size();
3120
3121 for (int cnt = 0 ; ; cnt ++, ioe ++) {
3122 // If the interface isn't implemented by the receiver class,
3123 // the VM should throw IncompatibleClassChangeError.
3124 if (cnt >= nof_interfaces) {
3125 ResourceMark rm(THREAD);
3126 stringStream ss;
3127 bool same_module = (module() == holder->module());
3128 ss.print("Receiver class %s does not implement "
3129 "the interface %s defining the method to be called "
3130 "(%s%s%s)",
3131 external_name(), holder->external_name(),
3132 (same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
3133 (same_module) ? "" : "; ",
3134 (same_module) ? "" : holder->class_in_module_of_loader());
3135 THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
3136 }
3137
3138 Klass* ik = ioe->interface_klass();
3139 if (ik == holder) break;
3140 }
3141
3142 itableMethodEntry* ime = ioe->first_method_entry(this);
3143 Method* m = ime[index].method();
3144 if (m == NULL) {
3145 THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
3146 }
3147 return m;
3148 }
3149
3150
3151 #if INCLUDE_JVMTI
3152 // update default_methods for redefineclasses for methods that are
3153 // not yet in the vtable due to concurrent subclass define and superinterface
3154 // redefinition
3155 // Note: those in the vtable, should have been updated via adjust_method_entries
3156 void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
3157 // search the default_methods for uses of either obsolete or EMCP methods
3158 if (default_methods() != NULL) {
3159 for (int index = 0; index < default_methods()->length(); index ++) {
3160 Method* old_method = default_methods()->at(index);
3161 if (old_method == NULL || !old_method->is_old()) {
3162 continue; // skip uninteresting entries
3163 }
3164 assert(!old_method->is_deleted(), "default methods may not be deleted");
3165 Method* new_method = old_method->get_new_method();
3166 default_methods()->at_put(index, new_method);
3167
3168 if (log_is_enabled(Info, redefine, class, update)) {
3169 ResourceMark rm;
3170 if (!(*trace_name_printed)) {
3171 log_info(redefine, class, update)
3172 ("adjust: klassname=%s default methods from name=%s",
3173 external_name(), old_method->method_holder()->external_name());
3174 *trace_name_printed = true;
3175 }
3176 log_debug(redefine, class, update, vtables)
3177 ("default method update: %s(%s) ",
3178 new_method->name()->as_C_string(), new_method->signature()->as_C_string());
3179 }
3180 }
3181 }
3182 }
3183 #endif // INCLUDE_JVMTI
3184
3185 // On-stack replacement stuff
3186 void InstanceKlass::add_osr_nmethod(nmethod* n) {
3187 assert_lock_strong(CompiledMethod_lock);
3188 #ifndef PRODUCT
3189 if (TieredCompilation) {
3190 nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
3191 assert(prev == NULL || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
3192 "redundant OSR recompilation detected. memory leak in CodeCache!");
3193 }
3194 #endif
3195 // only one compilation can be active
3196 {
3197 assert(n->is_osr_method(), "wrong kind of nmethod");
3198 n->set_osr_link(osr_nmethods_head());
3199 set_osr_nmethods_head(n);
3200 // Raise the highest osr level if necessary
3201 if (TieredCompilation) {
3202 Method* m = n->method();
3203 m->set_highest_osr_comp_level(MAX2(m->highest_osr_comp_level(), n->comp_level()));
3204 }
3205 }
3206
3207 // Get rid of the osr methods for the same bci that have lower levels.
3208 if (TieredCompilation) {
3209 for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
3210 nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
3211 if (inv != NULL && inv->is_in_use()) {
3212 inv->make_not_entrant();
3213 }
3214 }
3215 }
3216 }
3217
3218 // Remove osr nmethod from the list. Return true if found and removed.
3219 bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
3220 // This is a short non-blocking critical region, so the no safepoint check is ok.
3221 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock
3222 , Mutex::_no_safepoint_check_flag);
3223 assert(n->is_osr_method(), "wrong kind of nmethod");
3224 nmethod* last = NULL;
3225 nmethod* cur = osr_nmethods_head();
3226 int max_level = CompLevel_none; // Find the max comp level excluding n
3227 Method* m = n->method();
3228 // Search for match
3229 bool found = false;
3230 while(cur != NULL && cur != n) {
3231 if (TieredCompilation && m == cur->method()) {
3232 // Find max level before n
3233 max_level = MAX2(max_level, cur->comp_level());
3234 }
3235 last = cur;
3236 cur = cur->osr_link();
3237 }
3238 nmethod* next = NULL;
3239 if (cur == n) {
3240 found = true;
3241 next = cur->osr_link();
3242 if (last == NULL) {
3243 // Remove first element
3244 set_osr_nmethods_head(next);
3245 } else {
3246 last->set_osr_link(next);
3247 }
3248 }
3249 n->set_osr_link(NULL);
3250 if (TieredCompilation) {
3251 cur = next;
3252 while (cur != NULL) {
3253 // Find max level after n
3254 if (m == cur->method()) {
3255 max_level = MAX2(max_level, cur->comp_level());
3256 }
3257 cur = cur->osr_link();
3258 }
3259 m->set_highest_osr_comp_level(max_level);
3260 }
3261 return found;
3262 }
3263
3264 int InstanceKlass::mark_osr_nmethods(const Method* m) {
3265 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock,
3266 Mutex::_no_safepoint_check_flag);
3267 nmethod* osr = osr_nmethods_head();
3268 int found = 0;
3269 while (osr != NULL) {
3270 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3271 if (osr->method() == m) {
3272 osr->mark_for_deoptimization();
3273 found++;
3274 }
3275 osr = osr->osr_link();
3276 }
3277 return found;
3278 }
3279
3280 nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
3281 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock,
3282 Mutex::_no_safepoint_check_flag);
3283 nmethod* osr = osr_nmethods_head();
3284 nmethod* best = NULL;
3285 while (osr != NULL) {
3286 assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
3287 // There can be a time when a c1 osr method exists but we are waiting
3288 // for a c2 version. When c2 completes its osr nmethod we will trash
3289 // the c1 version and only be able to find the c2 version. However
3290 // while we overflow in the c1 code at back branches we don't want to
3291 // try and switch to the same code as we are already running
3292
3293 if (osr->method() == m &&
3294 (bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
3295 if (match_level) {
3296 if (osr->comp_level() == comp_level) {
3297 // Found a match - return it.
3298 return osr;
3299 }
3300 } else {
3301 if (best == NULL || (osr->comp_level() > best->comp_level())) {
3302 if (osr->comp_level() == CompLevel_highest_tier) {
3303 // Found the best possible - return it.
3304 return osr;
3305 }
3306 best = osr;
3307 }
3308 }
3309 }
3310 osr = osr->osr_link();
3311 }
3312
3313 assert(match_level == false || best == NULL, "shouldn't pick up anything if match_level is set");
3314 if (best != NULL && best->comp_level() >= comp_level) {
3315 return best;
3316 }
3317 return NULL;
3318 }
3319
3320 // -----------------------------------------------------------------------------------------------------
3321 // Printing
3322
3323 #ifndef PRODUCT
3324
3325 #define BULLET " - "
3326
3327 static const char* state_names[] = {
3328 "allocated", "loaded", "linked", "being_initialized", "fully_initialized", "initialization_error"
3329 };
3330
3331 static void print_vtable(intptr_t* start, int len, outputStream* st) {
3332 for (int i = 0; i < len; i++) {
3333 intptr_t e = start[i];
3334 st->print("%d : " INTPTR_FORMAT, i, e);
3335 if (MetaspaceObj::is_valid((Metadata*)e)) {
3336 st->print(" ");
3337 ((Metadata*)e)->print_value_on(st);
3338 }
3339 st->cr();
3340 }
3341 }
3342
3343 static void print_vtable(vtableEntry* start, int len, outputStream* st) {
3344 return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
3345 }
3346
3347 void InstanceKlass::print_on(outputStream* st) const {
3348 assert(is_klass(), "must be klass");
3349 Klass::print_on(st);
3350
3351 st->print(BULLET"instance size: %d", size_helper()); st->cr();
3352 st->print(BULLET"klass size: %d", size()); st->cr();
3353 st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
3354 st->print(BULLET"state: "); st->print_cr("%s", state_names[_init_state]);
3355 st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
3356 st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
3357 st->print(BULLET"sub: ");
3358 Klass* sub = subklass();
3359 int n;
3360 for (n = 0; sub != NULL; n++, sub = sub->next_sibling()) {
3361 if (n < MaxSubklassPrintSize) {
3362 sub->print_value_on(st);
3363 st->print(" ");
3364 }
3365 }
3366 if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
3367 st->cr();
3368
3369 if (is_interface()) {
3370 st->print_cr(BULLET"nof implementors: %d", nof_implementors());
3371 if (nof_implementors() == 1) {
3372 st->print_cr(BULLET"implementor: ");
3373 st->print(" ");
3374 implementor()->print_value_on(st);
3375 st->cr();
3376 }
3377 }
3378
3379 st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
3380 st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
3381 if (Verbose || WizardMode) {
3382 Array<Method*>* method_array = methods();
3383 for (int i = 0; i < method_array->length(); i++) {
3384 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3385 }
3386 }
3387 st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
3388 st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
3389 if (Verbose && default_methods() != NULL) {
3390 Array<Method*>* method_array = default_methods();
3391 for (int i = 0; i < method_array->length(); i++) {
3392 st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
3393 }
3394 }
3395 if (default_vtable_indices() != NULL) {
3396 st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
3397 }
3398 st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
3399 st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
3400 st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
3401 if (class_loader_data() != NULL) {
3402 st->print(BULLET"class loader data: ");
3403 class_loader_data()->print_value_on(st);
3404 st->cr();
3405 }
3406 st->print(BULLET"unsafe anonymous host class: "); Metadata::print_value_on_maybe_null(st, unsafe_anonymous_host()); st->cr();
3407 if (source_file_name() != NULL) {
3408 st->print(BULLET"source file: ");
3409 source_file_name()->print_value_on(st);
3410 st->cr();
3411 }
3412 if (source_debug_extension() != NULL) {
3413 st->print(BULLET"source debug extension: ");
3414 st->print("%s", source_debug_extension());
3415 st->cr();
3416 }
3417 st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
3418 st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
3419 st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
3420 st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
3421 {
3422 bool have_pv = false;
3423 // previous versions are linked together through the InstanceKlass
3424 for (InstanceKlass* pv_node = previous_versions();
3425 pv_node != NULL;
3426 pv_node = pv_node->previous_versions()) {
3427 if (!have_pv)
3428 st->print(BULLET"previous version: ");
3429 have_pv = true;
3430 pv_node->constants()->print_value_on(st);
3431 }
3432 if (have_pv) st->cr();
3433 }
3434
3435 if (generic_signature() != NULL) {
3436 st->print(BULLET"generic signature: ");
3437 generic_signature()->print_value_on(st);
3438 st->cr();
3439 }
3440 st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
3441 st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
3442 if (record_components() != NULL) {
3443 st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr();
3444 }
3445 st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
3446 if (java_mirror() != NULL) {
3447 st->print(BULLET"java mirror: ");
3448 java_mirror()->print_value_on(st);
3449 st->cr();
3450 } else {
3451 st->print_cr(BULLET"java mirror: NULL");
3452 }
3453 st->print(BULLET"vtable length %d (start addr: " INTPTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
3454 if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
3455 st->print(BULLET"itable length %d (start addr: " INTPTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
3456 if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
3457 st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
3458 FieldPrinter print_static_field(st);
3459 ((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
3460 st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
3461 FieldPrinter print_nonstatic_field(st);
3462 InstanceKlass* ik = const_cast<InstanceKlass*>(this);
3463 ik->do_nonstatic_fields(&print_nonstatic_field);
3464
3465 st->print(BULLET"non-static oop maps: ");
3466 OopMapBlock* map = start_of_nonstatic_oop_maps();
3467 OopMapBlock* end_map = map + nonstatic_oop_map_count();
3468 while (map < end_map) {
3469 st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
3470 map++;
3471 }
3472 st->cr();
3473 }
3474
3475 #endif //PRODUCT
3476
3477 void InstanceKlass::print_value_on(outputStream* st) const {
3478 assert(is_klass(), "must be klass");
3479 if (Verbose || WizardMode) access_flags().print_on(st);
3480 name()->print_value_on(st);
3481 }
3482
3483 #ifndef PRODUCT
3484
3485 void FieldPrinter::do_field(fieldDescriptor* fd) {
3486 _st->print(BULLET);
3487 if (_obj == NULL) {
3488 fd->print_on(_st);
3489 _st->cr();
3490 } else {
3491 fd->print_on_for(_st, _obj);
3492 _st->cr();
3493 }
3494 }
3495
3496
3497 void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
3498 Klass::oop_print_on(obj, st);
3499
3500 if (this == SystemDictionary::String_klass()) {
3501 typeArrayOop value = java_lang_String::value(obj);
3502 juint length = java_lang_String::length(obj);
3503 if (value != NULL &&
3504 value->is_typeArray() &&
3505 length <= (juint) value->length()) {
3506 st->print(BULLET"string: ");
3507 java_lang_String::print(obj, st);
3508 st->cr();
3509 if (!WizardMode) return; // that is enough
3510 }
3511 }
3512
3513 st->print_cr(BULLET"---- fields (total size %d words):", oop_size(obj));
3514 FieldPrinter print_field(st, obj);
3515 do_nonstatic_fields(&print_field);
3516
3517 if (this == SystemDictionary::Class_klass()) {
3518 st->print(BULLET"signature: ");
3519 java_lang_Class::print_signature(obj, st);
3520 st->cr();
3521 Klass* mirrored_klass = java_lang_Class::as_Klass(obj);
3522 st->print(BULLET"fake entry for mirror: ");
3523 Metadata::print_value_on_maybe_null(st, mirrored_klass);
3524 st->cr();
3525 Klass* array_klass = java_lang_Class::array_klass_acquire(obj);
3526 st->print(BULLET"fake entry for array: ");
3527 Metadata::print_value_on_maybe_null(st, array_klass);
3528 st->cr();
3529 st->print_cr(BULLET"fake entry for oop_size: %d", java_lang_Class::oop_size(obj));
3530 st->print_cr(BULLET"fake entry for static_oop_field_count: %d", java_lang_Class::static_oop_field_count(obj));
3531 Klass* real_klass = java_lang_Class::as_Klass(obj);
3532 if (real_klass != NULL && real_klass->is_instance_klass()) {
3533 InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
3534 }
3535 } else if (this == SystemDictionary::MethodType_klass()) {
3536 st->print(BULLET"signature: ");
3537 java_lang_invoke_MethodType::print_signature(obj, st);
3538 st->cr();
3539 }
3540 }
3541
3542 bool InstanceKlass::verify_itable_index(int i) {
3543 int method_count = klassItable::method_count_for_interface(this);
3544 assert(i >= 0 && i < method_count, "index out of bounds");
3545 return true;
3546 }
3547
3548 #endif //PRODUCT
3549
3550 void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
3551 st->print("a ");
3552 name()->print_value_on(st);
3553 obj->print_address_on(st);
3554 if (this == SystemDictionary::String_klass()
3555 && java_lang_String::value(obj) != NULL) {
3556 ResourceMark rm;
3557 int len = java_lang_String::length(obj);
3558 int plen = (len < 24 ? len : 12);
3559 char* str = java_lang_String::as_utf8_string(obj, 0, plen);
3560 st->print(" = \"%s\"", str);
3561 if (len > plen)
3562 st->print("...[%d]", len);
3563 } else if (this == SystemDictionary::Class_klass()) {
3564 Klass* k = java_lang_Class::as_Klass(obj);
3565 st->print(" = ");
3566 if (k != NULL) {
3567 k->print_value_on(st);
3568 } else {
3569 const char* tname = type2name(java_lang_Class::primitive_type(obj));
3570 st->print("%s", tname ? tname : "type?");
3571 }
3572 } else if (this == SystemDictionary::MethodType_klass()) {
3573 st->print(" = ");
3574 java_lang_invoke_MethodType::print_signature(obj, st);
3575 } else if (java_lang_boxing_object::is_instance(obj)) {
3576 st->print(" = ");
3577 java_lang_boxing_object::print(obj, st);
3578 } else if (this == SystemDictionary::LambdaForm_klass()) {
3579 oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
3580 if (vmentry != NULL) {
3581 st->print(" => ");
3582 vmentry->print_value_on(st);
3583 }
3584 } else if (this == SystemDictionary::MemberName_klass()) {
3585 Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
3586 if (vmtarget != NULL) {
3587 st->print(" = ");
3588 vmtarget->print_value_on(st);
3589 } else {
3590 java_lang_invoke_MemberName::clazz(obj)->print_value_on(st);
3591 st->print(".");
3592 java_lang_invoke_MemberName::name(obj)->print_value_on(st);
3593 }
3594 }
3595 }
3596
3597 const char* InstanceKlass::internal_name() const {
3598 return external_name();
3599 }
3600
3601 void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
3602 const char* module_name,
3603 const ClassFileStream* cfs) const {
3604 if (!log_is_enabled(Info, class, load)) {
3605 return;
3606 }
3607
3608 ResourceMark rm;
3609 LogMessage(class, load) msg;
3610 stringStream info_stream;
3611
3612 // Name and class hierarchy info
3613 info_stream.print("%s", external_name());
3614
3615 // Source
3616 if (cfs != NULL) {
3617 if (cfs->source() != NULL) {
3618 if (module_name != NULL) {
3619 // When the boot loader created the stream, it didn't know the module name
3620 // yet. Let's format it now.
3621 if (cfs->from_boot_loader_modules_image()) {
3622 info_stream.print(" source: jrt:/%s", module_name);
3623 } else {
3624 info_stream.print(" source: %s", cfs->source());
3625 }
3626 } else {
3627 info_stream.print(" source: %s", cfs->source());
3628 }
3629 } else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
3630 Thread* THREAD = Thread::current();
3631 Klass* caller =
3632 THREAD->is_Java_thread()
3633 ? ((JavaThread*)THREAD)->security_get_caller_class(1)
3634 : NULL;
3635 // caller can be NULL, for example, during a JVMTI VM_Init hook
3636 if (caller != NULL) {
3637 info_stream.print(" source: instance of %s", caller->external_name());
3638 } else {
3639 // source is unknown
3640 }
3641 } else {
3642 oop class_loader = loader_data->class_loader();
3643 info_stream.print(" source: %s", class_loader->klass()->external_name());
3644 }
3645 } else {
3646 assert(this->is_shared(), "must be");
3647 if (MetaspaceShared::is_shared_dynamic((void*)this)) {
3648 info_stream.print(" source: shared objects file (top)");
3649 } else {
3650 info_stream.print(" source: shared objects file");
3651 }
3652 }
3653
3654 msg.info("%s", info_stream.as_string());
3655
3656 if (log_is_enabled(Debug, class, load)) {
3657 stringStream debug_stream;
3658
3659 // Class hierarchy info
3660 debug_stream.print(" klass: " INTPTR_FORMAT " super: " INTPTR_FORMAT,
3661 p2i(this), p2i(superklass()));
3662
3663 // Interfaces
3664 if (local_interfaces() != NULL && local_interfaces()->length() > 0) {
3665 debug_stream.print(" interfaces:");
3666 int length = local_interfaces()->length();
3667 for (int i = 0; i < length; i++) {
3668 debug_stream.print(" " INTPTR_FORMAT,
3669 p2i(InstanceKlass::cast(local_interfaces()->at(i))));
3670 }
3671 }
3672
3673 // Class loader
3674 debug_stream.print(" loader: [");
3675 loader_data->print_value_on(&debug_stream);
3676 debug_stream.print("]");
3677
3678 // Classfile checksum
3679 if (cfs) {
3680 debug_stream.print(" bytes: %d checksum: %08x",
3681 cfs->length(),
3682 ClassLoader::crc32(0, (const char*)cfs->buffer(),
3683 cfs->length()));
3684 }
3685
3686 msg.debug("%s", debug_stream.as_string());
3687 }
3688 }
3689
3690 // Verification
3691
3692 class VerifyFieldClosure: public BasicOopIterateClosure {
3693 protected:
3694 template <class T> void do_oop_work(T* p) {
3695 oop obj = RawAccess<>::oop_load(p);
3696 if (!oopDesc::is_oop_or_null(obj)) {
3697 tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
3698 Universe::print_on(tty);
3699 guarantee(false, "boom");
3700 }
3701 }
3702 public:
3703 virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
3704 virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
3705 };
3706
3707 void InstanceKlass::verify_on(outputStream* st) {
3708 #ifndef PRODUCT
3709 // Avoid redundant verifies, this really should be in product.
3710 if (_verify_count == Universe::verify_count()) return;
3711 _verify_count = Universe::verify_count();
3712 #endif
3713
3714 // Verify Klass
3715 Klass::verify_on(st);
3716
3717 // Verify that klass is present in ClassLoaderData
3718 guarantee(class_loader_data()->contains_klass(this),
3719 "this class isn't found in class loader data");
3720
3721 // Verify vtables
3722 if (is_linked()) {
3723 // $$$ This used to be done only for m/s collections. Doing it
3724 // always seemed a valid generalization. (DLD -- 6/00)
3725 vtable().verify(st);
3726 }
3727
3728 // Verify first subklass
3729 if (subklass() != NULL) {
3730 guarantee(subklass()->is_klass(), "should be klass");
3731 }
3732
3733 // Verify siblings
3734 Klass* super = this->super();
3735 Klass* sib = next_sibling();
3736 if (sib != NULL) {
3737 if (sib == this) {
3738 fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
3739 }
3740
3741 guarantee(sib->is_klass(), "should be klass");
3742 guarantee(sib->super() == super, "siblings should have same superklass");
3743 }
3744
3745 // Verify local interfaces
3746 if (local_interfaces()) {
3747 Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
3748 for (int j = 0; j < local_interfaces->length(); j++) {
3749 InstanceKlass* e = local_interfaces->at(j);
3750 guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
3751 }
3752 }
3753
3754 // Verify transitive interfaces
3755 if (transitive_interfaces() != NULL) {
3756 Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
3757 for (int j = 0; j < transitive_interfaces->length(); j++) {
3758 InstanceKlass* e = transitive_interfaces->at(j);
3759 guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
3760 }
3761 }
3762
3763 // Verify methods
3764 if (methods() != NULL) {
3765 Array<Method*>* methods = this->methods();
3766 for (int j = 0; j < methods->length(); j++) {
3767 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3768 }
3769 for (int j = 0; j < methods->length() - 1; j++) {
3770 Method* m1 = methods->at(j);
3771 Method* m2 = methods->at(j + 1);
3772 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3773 }
3774 }
3775
3776 // Verify method ordering
3777 if (method_ordering() != NULL) {
3778 Array<int>* method_ordering = this->method_ordering();
3779 int length = method_ordering->length();
3780 if (JvmtiExport::can_maintain_original_method_order() ||
3781 ((UseSharedSpaces || Arguments::is_dumping_archive()) && length != 0)) {
3782 guarantee(length == methods()->length(), "invalid method ordering length");
3783 jlong sum = 0;
3784 for (int j = 0; j < length; j++) {
3785 int original_index = method_ordering->at(j);
3786 guarantee(original_index >= 0, "invalid method ordering index");
3787 guarantee(original_index < length, "invalid method ordering index");
3788 sum += original_index;
3789 }
3790 // Verify sum of indices 0,1,...,length-1
3791 guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
3792 } else {
3793 guarantee(length == 0, "invalid method ordering length");
3794 }
3795 }
3796
3797 // Verify default methods
3798 if (default_methods() != NULL) {
3799 Array<Method*>* methods = this->default_methods();
3800 for (int j = 0; j < methods->length(); j++) {
3801 guarantee(methods->at(j)->is_method(), "non-method in methods array");
3802 }
3803 for (int j = 0; j < methods->length() - 1; j++) {
3804 Method* m1 = methods->at(j);
3805 Method* m2 = methods->at(j + 1);
3806 guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
3807 }
3808 }
3809
3810 // Verify JNI static field identifiers
3811 if (jni_ids() != NULL) {
3812 jni_ids()->verify(this);
3813 }
3814
3815 // Verify other fields
3816 if (constants() != NULL) {
3817 guarantee(constants()->is_constantPool(), "should be constant pool");
3818 }
3819 const Klass* anonymous_host = unsafe_anonymous_host();
3820 if (anonymous_host != NULL) {
3821 guarantee(anonymous_host->is_klass(), "should be klass");
3822 }
3823 }
3824
3825 void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
3826 Klass::oop_verify_on(obj, st);
3827 VerifyFieldClosure blk;
3828 obj->oop_iterate(&blk);
3829 }
3830
3831
3832 // JNIid class for jfieldIDs only
3833 // Note to reviewers:
3834 // These JNI functions are just moved over to column 1 and not changed
3835 // in the compressed oops workspace.
3836 JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
3837 _holder = holder;
3838 _offset = offset;
3839 _next = next;
3840 debug_only(_is_static_field_id = false;)
3841 }
3842
3843
3844 JNIid* JNIid::find(int offset) {
3845 JNIid* current = this;
3846 while (current != NULL) {
3847 if (current->offset() == offset) return current;
3848 current = current->next();
3849 }
3850 return NULL;
3851 }
3852
3853 void JNIid::deallocate(JNIid* current) {
3854 while (current != NULL) {
3855 JNIid* next = current->next();
3856 delete current;
3857 current = next;
3858 }
3859 }
3860
3861
3862 void JNIid::verify(Klass* holder) {
3863 int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
3864 int end_field_offset;
3865 end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
3866
3867 JNIid* current = this;
3868 while (current != NULL) {
3869 guarantee(current->holder() == holder, "Invalid klass in JNIid");
3870 #ifdef ASSERT
3871 int o = current->offset();
3872 if (current->is_static_field_id()) {
3873 guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
3874 }
3875 #endif
3876 current = current->next();
3877 }
3878 }
3879
3880 void InstanceKlass::set_init_state(ClassState state) {
3881 #ifdef ASSERT
3882 bool good_state = is_shared() ? (_init_state <= state)
3883 : (_init_state < state);
3884 assert(good_state || state == allocated, "illegal state transition");
3885 #endif
3886 assert(_init_thread == NULL, "should be cleared before state change");
3887 _init_state = (u1)state;
3888 }
3889
3890 #if INCLUDE_JVMTI
3891
3892 // RedefineClasses() support for previous versions
3893
3894 // Globally, there is at least one previous version of a class to walk
3895 // during class unloading, which is saved because old methods in the class
3896 // are still running. Otherwise the previous version list is cleaned up.
3897 bool InstanceKlass::_has_previous_versions = false;
3898
3899 // Returns true if there are previous versions of a class for class
3900 // unloading only. Also resets the flag to false. purge_previous_version
3901 // will set the flag to true if there are any left, i.e., if there's any
3902 // work to do for next time. This is to avoid the expensive code cache
3903 // walk in CLDG::clean_deallocate_lists().
3904 bool InstanceKlass::has_previous_versions_and_reset() {
3905 bool ret = _has_previous_versions;
3906 log_trace(redefine, class, iklass, purge)("Class unloading: has_previous_versions = %s",
3907 ret ? "true" : "false");
3908 _has_previous_versions = false;
3909 return ret;
3910 }
3911
3912 // Purge previous versions before adding new previous versions of the class and
3913 // during class unloading.
3914 void InstanceKlass::purge_previous_version_list() {
3915 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
3916 assert(has_been_redefined(), "Should only be called for main class");
3917
3918 // Quick exit.
3919 if (previous_versions() == NULL) {
3920 return;
3921 }
3922
3923 // This klass has previous versions so see what we can cleanup
3924 // while it is safe to do so.
3925
3926 int deleted_count = 0; // leave debugging breadcrumbs
3927 int live_count = 0;
3928 ClassLoaderData* loader_data = class_loader_data();
3929 assert(loader_data != NULL, "should never be null");
3930
3931 ResourceMark rm;
3932 log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
3933
3934 // previous versions are linked together through the InstanceKlass
3935 InstanceKlass* pv_node = previous_versions();
3936 InstanceKlass* last = this;
3937 int version = 0;
3938
3939 // check the previous versions list
3940 for (; pv_node != NULL; ) {
3941
3942 ConstantPool* pvcp = pv_node->constants();
3943 assert(pvcp != NULL, "cp ref was unexpectedly cleared");
3944
3945 if (!pvcp->on_stack()) {
3946 // If the constant pool isn't on stack, none of the methods
3947 // are executing. Unlink this previous_version.
3948 // The previous version InstanceKlass is on the ClassLoaderData deallocate list
3949 // so will be deallocated during the next phase of class unloading.
3950 log_trace(redefine, class, iklass, purge)
3951 ("previous version " INTPTR_FORMAT " is dead.", p2i(pv_node));
3952 // For debugging purposes.
3953 pv_node->set_is_scratch_class();
3954 // Unlink from previous version list.
3955 assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
3956 InstanceKlass* next = pv_node->previous_versions();
3957 pv_node->link_previous_versions(NULL); // point next to NULL
3958 last->link_previous_versions(next);
3959 // Add to the deallocate list after unlinking
3960 loader_data->add_to_deallocate_list(pv_node);
3961 pv_node = next;
3962 deleted_count++;
3963 version++;
3964 continue;
3965 } else {
3966 log_trace(redefine, class, iklass, purge)("previous version " INTPTR_FORMAT " is alive", p2i(pv_node));
3967 assert(pvcp->pool_holder() != NULL, "Constant pool with no holder");
3968 guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
3969 live_count++;
3970 // found a previous version for next time we do class unloading
3971 _has_previous_versions = true;
3972 }
3973
3974 // At least one method is live in this previous version.
3975 // Reset dead EMCP methods not to get breakpoints.
3976 // All methods are deallocated when all of the methods for this class are no
3977 // longer running.
3978 Array<Method*>* method_refs = pv_node->methods();
3979 if (method_refs != NULL) {
3980 log_trace(redefine, class, iklass, purge)("previous methods length=%d", method_refs->length());
3981 for (int j = 0; j < method_refs->length(); j++) {
3982 Method* method = method_refs->at(j);
3983
3984 if (!method->on_stack()) {
3985 // no breakpoints for non-running methods
3986 if (method->is_running_emcp()) {
3987 method->set_running_emcp(false);
3988 }
3989 } else {
3990 assert (method->is_obsolete() || method->is_running_emcp(),
3991 "emcp method cannot run after emcp bit is cleared");
3992 log_trace(redefine, class, iklass, purge)
3993 ("purge: %s(%s): prev method @%d in version @%d is alive",
3994 method->name()->as_C_string(), method->signature()->as_C_string(), j, version);
3995 }
3996 }
3997 }
3998 // next previous version
3999 last = pv_node;
4000 pv_node = pv_node->previous_versions();
4001 version++;
4002 }
4003 log_trace(redefine, class, iklass, purge)
4004 ("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
4005 }
4006
4007 void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
4008 int emcp_method_count) {
4009 int obsolete_method_count = old_methods->length() - emcp_method_count;
4010
4011 if (emcp_method_count != 0 && obsolete_method_count != 0 &&
4012 _previous_versions != NULL) {
4013 // We have a mix of obsolete and EMCP methods so we have to
4014 // clear out any matching EMCP method entries the hard way.
4015 int local_count = 0;
4016 for (int i = 0; i < old_methods->length(); i++) {
4017 Method* old_method = old_methods->at(i);
4018 if (old_method->is_obsolete()) {
4019 // only obsolete methods are interesting
4020 Symbol* m_name = old_method->name();
4021 Symbol* m_signature = old_method->signature();
4022
4023 // previous versions are linked together through the InstanceKlass
4024 int j = 0;
4025 for (InstanceKlass* prev_version = _previous_versions;
4026 prev_version != NULL;
4027 prev_version = prev_version->previous_versions(), j++) {
4028
4029 Array<Method*>* method_refs = prev_version->methods();
4030 for (int k = 0; k < method_refs->length(); k++) {
4031 Method* method = method_refs->at(k);
4032
4033 if (!method->is_obsolete() &&
4034 method->name() == m_name &&
4035 method->signature() == m_signature) {
4036 // The current RedefineClasses() call has made all EMCP
4037 // versions of this method obsolete so mark it as obsolete
4038 log_trace(redefine, class, iklass, add)
4039 ("%s(%s): flush obsolete method @%d in version @%d",
4040 m_name->as_C_string(), m_signature->as_C_string(), k, j);
4041
4042 method->set_is_obsolete();
4043 break;
4044 }
4045 }
4046
4047 // The previous loop may not find a matching EMCP method, but
4048 // that doesn't mean that we can optimize and not go any
4049 // further back in the PreviousVersion generations. The EMCP
4050 // method for this generation could have already been made obsolete,
4051 // but there still may be an older EMCP method that has not
4052 // been made obsolete.
4053 }
4054
4055 if (++local_count >= obsolete_method_count) {
4056 // no more obsolete methods so bail out now
4057 break;
4058 }
4059 }
4060 }
4061 }
4062 }
4063
4064 // Save the scratch_class as the previous version if any of the methods are running.
4065 // The previous_versions are used to set breakpoints in EMCP methods and they are
4066 // also used to clean MethodData links to redefined methods that are no longer running.
4067 void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
4068 int emcp_method_count) {
4069 assert(Thread::current()->is_VM_thread(),
4070 "only VMThread can add previous versions");
4071
4072 ResourceMark rm;
4073 log_trace(redefine, class, iklass, add)
4074 ("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
4075
4076 // Clean out old previous versions for this class
4077 purge_previous_version_list();
4078
4079 // Mark newly obsolete methods in remaining previous versions. An EMCP method from
4080 // a previous redefinition may be made obsolete by this redefinition.
4081 Array<Method*>* old_methods = scratch_class->methods();
4082 mark_newly_obsolete_methods(old_methods, emcp_method_count);
4083
4084 // If the constant pool for this previous version of the class
4085 // is not marked as being on the stack, then none of the methods
4086 // in this previous version of the class are on the stack so
4087 // we don't need to add this as a previous version.
4088 ConstantPool* cp_ref = scratch_class->constants();
4089 if (!cp_ref->on_stack()) {
4090 log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
4091 // For debugging purposes.
4092 scratch_class->set_is_scratch_class();
4093 scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
4094 return;
4095 }
4096
4097 if (emcp_method_count != 0) {
4098 // At least one method is still running, check for EMCP methods
4099 for (int i = 0; i < old_methods->length(); i++) {
4100 Method* old_method = old_methods->at(i);
4101 if (!old_method->is_obsolete() && old_method->on_stack()) {
4102 // if EMCP method (not obsolete) is on the stack, mark as EMCP so that
4103 // we can add breakpoints for it.
4104
4105 // We set the method->on_stack bit during safepoints for class redefinition
4106 // and use this bit to set the is_running_emcp bit.
4107 // After the safepoint, the on_stack bit is cleared and the running emcp
4108 // method may exit. If so, we would set a breakpoint in a method that
4109 // is never reached, but this won't be noticeable to the programmer.
4110 old_method->set_running_emcp(true);
4111 log_trace(redefine, class, iklass, add)
4112 ("EMCP method %s is on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
4113 } else if (!old_method->is_obsolete()) {
4114 log_trace(redefine, class, iklass, add)
4115 ("EMCP method %s is NOT on_stack " INTPTR_FORMAT, old_method->name_and_sig_as_C_string(), p2i(old_method));
4116 }
4117 }
4118 }
4119
4120 // Add previous version if any methods are still running.
4121 // Set has_previous_version flag for processing during class unloading.
4122 _has_previous_versions = true;
4123 log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
4124 assert(scratch_class->previous_versions() == NULL, "shouldn't have a previous version");
4125 scratch_class->link_previous_versions(previous_versions());
4126 link_previous_versions(scratch_class);
4127 } // end add_previous_version()
4128
4129 #endif // INCLUDE_JVMTI
4130
4131 Method* InstanceKlass::method_with_idnum(int idnum) {
4132 Method* m = NULL;
4133 if (idnum < methods()->length()) {
4134 m = methods()->at(idnum);
4135 }
4136 if (m == NULL || m->method_idnum() != idnum) {
4137 for (int index = 0; index < methods()->length(); ++index) {
4138 m = methods()->at(index);
4139 if (m->method_idnum() == idnum) {
4140 return m;
4141 }
4142 }
4143 // None found, return null for the caller to handle.
4144 return NULL;
4145 }
4146 return m;
4147 }
4148
4149
4150 Method* InstanceKlass::method_with_orig_idnum(int idnum) {
4151 if (idnum >= methods()->length()) {
4152 return NULL;
4153 }
4154 Method* m = methods()->at(idnum);
4155 if (m != NULL && m->orig_method_idnum() == idnum) {
4156 return m;
4157 }
4158 // Obsolete method idnum does not match the original idnum
4159 for (int index = 0; index < methods()->length(); ++index) {
4160 m = methods()->at(index);
4161 if (m->orig_method_idnum() == idnum) {
4162 return m;
4163 }
4164 }
4165 // None found, return null for the caller to handle.
4166 return NULL;
4167 }
4168
4169
4170 Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
4171 InstanceKlass* holder = get_klass_version(version);
4172 if (holder == NULL) {
4173 return NULL; // The version of klass is gone, no method is found
4174 }
4175 Method* method = holder->method_with_orig_idnum(idnum);
4176 return method;
4177 }
4178
4179 #if INCLUDE_JVMTI
4180 JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
4181 return _cached_class_file;
4182 }
4183
4184 jint InstanceKlass::get_cached_class_file_len() {
4185 return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
4186 }
4187
4188 unsigned char * InstanceKlass::get_cached_class_file_bytes() {
4189 return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
4190 }
4191 #endif